Edited by Shane R. Jimerson, Ph.D.
Contributed to by the Graduate Students in the Counseling, Clinical,
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Ongoing design and publication of this site is completed by Shane R.
Jimerson, Jeff R. Klein and Angela D. Whipple. Please forward comments
regarding this site to Shane
R. Jimerson. This
page was last updated 1.11.02. ©
2002
Symptoms
Epidemiology
Etiology
Assessment
Treatment
Authors:
Shane R. Jimerson, Susan Ko, & Joyce Ester
University of California, Santa Barbara
The authors also note the important contributions of Chelsea Buckley and Benny Martin, who provided information critical to the development of this website.
Tourette's Disorder
Tourette's Disorder (TD) is a neuropsychiatric
disorder with a childhood onset. Current conceptualization considers
TD as lying at one extreme end of a continuum of tic disorders with the
most florid symptoms. Although cases of TD have been reported for
centuries (Kushner, 1999), the relative rarity of the disorder has contributed
to the lack of knowledge and understanding by the general public as well
as clinicians.
Tourette's Disorder warrants the interest
of clinicians who work with children because of its frequent association
with school failure and conditions such as attention-deficit/hyperactivity
disorder (ADHD; Comings & Comings, 1984), obsessive-compulsive disorder
(OCD; Frankel et al., 1986) and autism (Baron-Cohen, Mortimore, Moriarty,
et al., 1999). Additionally, social, academic, and occupational functioning
may be impaired due to misinterpretation of symptoms by others and the
child or adolescent's anxiety about not being able to control tics in social
situations. Some children with Tourette’s disorder experience peer and
adaptive difficulties (Dykens et al. 1999). In a 1991 study by Stokes et
al., they found that relative to same-sex peers, children with Tourette’s
were significantly more withdrawn and less popular or well liked.
Findings such as these speak to the difficulties that children with Tourette’s
face in the school and social environments.
In severe cases of Tourette's Disorder, the
tics may directly interfere with daily activities (e.g., reading or writing).
Rare complications of Tourette's Disorder include physical injury, such
as blindness due to retinal detachment (from head banging or striking oneself),
orthopedic problems (from knee bending, neck jerking, or head turning),
and skin problems (from picking). This disorder should be of particular
interest to those working with children because of the early age of onset
(usually 7-9 years of age) and the disturbing finding that an accurate
diagnosis of Tourette's Disorder often occurs 5-12 years after the onset
of initial symptoms (Golden & Hood, 1982).
Because of the often disruptive nature of
this disorder, children may have difficulty in social situations with their
peers. The symptoms of the disorder may make the child or adolescent
vulnerable to ostracism by peers. Aside from the physical harm that
the disordered child may do to him/herself, there may be incidents of physical
aggression toward others. Because some tics have an aggressive and/or sexual
component, the child or adolescent may experience social consequences (Kaplan
& Sadock, 1998).
Tourette's Disorder is one of four tic disorders
listed in the DSM-IV (American Psychiatric Association, 1994).
A tic is a sudden, rapid, recurrent, nonrhythmic, stereotyped motor movement
or vocalization that is experienced as irresistible and involuntary but
can be suppressed for varying lengths of time. The tics typically involve
the head and, frequently, other parts of the body, such as the torso and
limbs. Vocal tics include clicks, grunts, yelps, barks, sniffs, snorts,
and coughs. Coprolalia, a complex vocal tic involving the uttering of obscenities,
is present in less than 10% of individuals with this disorder. See
Table 1 for the full DSM-IV-TR diagnostic criteria.
Complex motor tics may be present, such as
touching, squatting, deep knee bends, retracing steps, and twirling when
walking. In one-half of the individuals with this disorder, the first symptoms
to appear are bouts of a single tic, most frequently eye blinking or less
often other facial or body tics. Initial symptoms can also include tongue
protrusion, squatting, sniffing, hopping, skipping, throat clearing, stuttering,
uttering sounds or words, and coprolalia. The other cases begin with multiple
symptoms and disorders.
DSM-IV-TR Criteria for Tourette's Disorder
The diagnostic criteria according to the DSM-IV-TR (APA, 2000) for 307.23
Tourette's Syndrome:
(A) Both multiple motor and one or more vocal tics have been
present at some time during the illness, although not necessarily concurrently.
(A tic is a sudden, rapid, recurrent, nonrythmic, stereotyped motor movement
or vocalization.)
(B) The tics occur many times a day (usually in bouts) nearly
every day or intermittently throughout a period of more than 1 year, and
during this period there was never a tic-free period of more than 3 consecutive
months.
(C) The onset is before age 18 years.
(D) The disturbance is not due to the direct physiological effects
of a substance (e.g., stimulants) or a general medical condition (e.g..
Huntington’s disease or postviral encephalitis).
EPIDEMIOLOGY
The prevalence for this disorder is disputed
and varies according to the methodology used to collect the epidemiological
data. Difficulty in gathering this data stems from the relative rarity
of the disorder among the general population and the waxing and waning
of symptoms that make diagnosis difficult. Early estimates ranged
from 1.9-49.5 per 10,000 (Zahner, Clubb, Leckman, & Pauls, 1988).
However, these measurements were based on treatment populations in outpatient,
inpatient and child guidance centers and were therefore influenced by selection
bias. These figures should be interpreted as the rate one would
come across a case of Tourette's if working in a clinical setting.
In studies using community sampling, estimates range from 4.9-9.3 per 10,000
males and 1.0-3.1 per 10,000 females (Burd, Kerbeshian, Wikenheiser, &
Fisher, 1986; Apter, Pauls, Bleich, et al., 1993).
In the course of time and progression of the
symptoms, there can be periods of remission, variable expressivity and
severity decreasing with time over the life span. Symptoms often
diminish significantly in adolescence and may disappear altogether by early
adulthood. However, if the disorder continues into adulthood, the
likelihood of remission diminishes (Sallee & Spratt, 1998).
The median age for onset is 7 years, occurring
as early as 2 years or as old as 18. For every female diagnosed with
this disorder, there is an average of 1.5 to 3 males. Occurrences
of the syndrome are reported in diverse racial and ethnic groups (Staley,
Wand & Shady, 1997). There are differentiated phenotypes ranging from
the full manifestation of Tourette symptoms to differing combinations of
the features of Obsessive Compulsive Disorder, Attention-Deficit/Hyperactivity
Disorder, and Chronic Motor or Vocal Tic Disorder. However, in 10%
of cases of Tourette Syndrome, there is no genetic involvement, but these
instances usually accompany other mental disorders or medical conditions.
Baron-Cohen and colleagues (1999) recently
examined the prevalence of Tourette's Disorder among children with autism
through an empirical study. The authors stated that despite growing
case reports of TS with autism, studies examining the prevalence of comorbid
autism and TS have been rare. The number of children diagnosed with
both autism and TS were higher than expected by chance (8.1% of a sample
of children with autism who had not previously been diagnosed with TS).
Although limited by a small sample size (n=37), the implications of the
study are important. For example, the study emphasized the need for
researchers to make careful assessment and recommended observation on several
different occasions as well as interviews with family for more accurate
diagnosis to create a more precise picture of the prevalence of the disorder.
Even so, the variable nature of tics makes an accurate count difficult
and the authors argued that, despite the limitation of small sample size,
the current study's estimate is an underestimation.
Walter and Carter's (1997) article discusses
the history, clinical presentation, etiology, associated symptoms and difficulties,
assessment, intervention, pharmacotherapy, behavior modification, and recommendations
for school settings for Tourette's Syndrome. The authors describe
the general characteristics of children with Tourette's, as well as variability
that might occur among children. The lack of knowledge of a precise
etiology was reviewed, as was the possible genetic and neurobiologic research
being conducted. In addition to illustrating Tourette's Syndrome
in detail, the article also reported on commonly associated symptoms, such
as OCD and ADHD, and the assessment and intervention of them. Finally,
this article explains methods by which the school psychologist could implement
classroom modifications or other means to increase the learning by children
with Tourette's Syndrome.
Wodrich (1998) argues the need for school
psychologists to be more aware of Tourette's and tic disorders because
of their link to school failure and other significant comorbid conditions
such as obsessive-compulsive disorder, ADHD, and learning disabilities.
The article answered clearly some common questions about Tourette's Disorder
(e.g., How common are these disorders? Are there viable treatment options?)
and argued that school psychologists could play an important role in the
early detection of tic disorders as well as in implementation of treatment.
Although pharmacological treatment is typically prescribed, the author
suggests that school psychologists could assist in the assessment of social
functioning as well as help the child deal with other stigmatizing aspects
of the disorder.
Conclusion
Although most researchers agree that Tourette's
Syndrome is principally a genetic disorder, the precise etiology and the
possible genetic links to such disorders as OCD, ADHD, autism, and learning
disabilities are still under examination by researchers. Additionally,
better methodology is currently being used in prevalence and epidemiological
studies to provide a more accurate picture of the prevalence of Tourette's
Disorder. Despite the questions that remain about the etiology and
prevalence of Tourette's Disorder, the close link between Tourette's and
school failure and other significant co-morbid disorders indicates that
those who work with children should be educated about the condition.
Because of the nature of the tics and the sometimes anti-social ways in
which they can be expressed, the child's actions may often be misinterpreted
as anti-social or annoying behavior under the volition of the child.
This stigmatizing aspect of the disorder may be lead to undue punishment
and social ostracism. The social and cognitive aspects of the disorder
need to be addressed in treatment as well as the reduction of tics.
Currently, there is less research on the efficacy of treatment for these
secondary features of Tourette's and most of the treatment efficacy literature
focuses on drug interventions to diminish tics.
I. ETIOLOGY
Etiology refers to the factors and variables
that predispose, precipitate and perpetuate a disorder. According
to the DSM-IV (APA,1994), Tourette's Disorder "is not due to the direct
physiological effects of a substance (e.g., stimulants) or a general medical
condition (e.g., Huntington's disease or postviral encephalitis".
To support the genetic etiology of Tourette's Disorder, twin studies, adoption
studies, and segregation analysis have been used(Kaplan and Saddock, 1998).
Although the precise etiology of TD is unknown, tics are believed to result
from multiple dysfunction in the central nervous system (Budman, et al,
2000). Historically, in the case of Tourette's disorder (TD), psychological
models attempted to explain the symptoms as manifestations of unresolved,
unconscious psychological conflicts, usually pertaining to sex or aggression
(Kushner, 1999). Those ascribing to this model cited the seeming
ability of those suffering from TD to be able to control their tics and
the negative effect of stress on the severity of tics.
Currently, the consensus holds that
TD is an organic disorder affected by genetic, neurobiological and epigenetic
(or environmental) variables. Efforts to research the underlying
causes of this disorder have been hampered by difficulties in definition
as researchers and clinicians found it difficult to decide which symptoms
should be included in its classification. Currently, there
is general agreement that there is a continuum of tic disorders that vary
in the chronicity, severity, and the duration of tics, with Tourette's
being the most florid expression of the disorder in this continuum (Hyde
& Weinberger, 1995). The articles below provide the clinician
with an overview of the current genetic and neurobiological research currently
being conducted. Additionally, reviews of articles examining the
family, social, and psychological influences that also affect the expression
of Tourette's disorder are highlighted.
Biological/Genetic
Recently, Lichter, Dmochowski, Jackson, &
Trinidad (1999) questioned the generally accepted theory that TD is transmitted
primarily through an autosomal dominant pattern with reduced penetrance.
They argued that other transmission patterns, such as a "semidominant-semirecessive"
pattern, may result in pedigree patterns that are indistinguishable from
those resulting from an autosomal dominant trait with reduced penetrance.
Their empirical study examined whether expression of TD may be influenced
by bilineal (i.e., genetic contributions from both sides of the family)
transmission since this implies recessive or polygenic inheritance-transmission
patterns that are common in complex neuropsychiatric disorders. The
researchers used family history methodology, including interviews with
relatives of patients, and compared those with a family history of TS with
those who did not to determine the frequency of unilineal (i.e., genetic
transmission from one side of the family only) and bilineal transmission
in each case. They determined that bilineal transmission of tics
is relatively infrequent, although cotransmission of obsessive-compulsive
behavior was quite common and significantly influenced development of obsessive-compulsive
and self-injurious behaviors, but not tics, in offspring. The authors
suggest that epigenetic factors and gene-environment interactions may play
a more important role than genetic dosage effects in determining tic severity
in TD.
Leckman and Cohen's (1999) book, Tourette's
Syndrome-Tics, Obsessions, Compulsions, pulls together 25 years of research
on the etiology and treatment of TD. Pauls, Alsobrook, Gelernter,
and Leckman's (1999) chapter on genetic factors reviews current research
on the TD vulnerability genes. It also discusses the genetic expression
of Tourette's and Obsessive Compulsive Disorder then proffers some evidence
for the possible common genetic linkages between the two disorders.
The possibility of TD being genetically connected to ADHD is also examined.
Future directions in genetic research are highlighted.
Sheppard, Bradshaw, Purcell, & Pantelis
(1999) examined the possibility of a common etiology among TD, obsessive
compulsive disorder, and ADHD by reviewing neuroimaging studies.
They found that all three disorders involve neuropathology of the basal-ganglia
thalamocortical pathway, but were associated with different circuits within
this pathway (e.g., TD was associated with pathology in the sensorimotor
and limbic circuits while OCD was associated with the prefrontal and limbic
circuits). They noted the similarities in the primary symptoms of
the three disorders and contend that they may all be considered disorders
of disinhibition. When comparing the primary symptoms of TD
an OCD, the authors suggest that OCD is the cognitive counterpart to the
motor disorder of TD. They suggest that the gene(s) responsible for TD
are at least responsible for an increased susceptibility to both OCD and
ADHD, maybe due to the overlap in the neuropathology. Shepard, et
al. Point out that over 60% of TD patients may develop OC symptoms and
30-50% of the TD patients meet the diagnostic criteria for OCD. However,
they point out that more research is necessary to determine why the neurochemical
environment in a TD brain may cause this predisposition to OCD or ADHD
behaviors.
In their article, "Explosive outbursts in
Children with Tourette's Disorder", Budman, Bruun, Park, Lesser, &
Olson address the relationship between explosive outbursts, Tourette's
Disorder, and it's comorbid disorders. Findings from their 2 year
study of children with TD between the ages of 6 & 16, shows a high
frequency of ADHD in the experimental group (95%) compared with the control
group (65%). Similar findings were made with regard to OCD (92% in
the experimental group and 71% in the control group). Aside from
ADHD and OCD, Budman and her colleagues found occurrences of mood disorder
(29%), depression (42%), and dysthymia (18%). The authors conclude
that the probability of the explosive outbursts in TD is greatly enhanced
by the presence of comorbid conditions. The further contend that
explosive outbursts increase with the increased number of comorbid conditions.
Comings (1997) reviews the evidence to support
the concept that many childhood and adolescent disruptive behaviors, including
Tourette's syndrome and ADHD, are part of a spectrum of interrelated behaviors
that have a strong genetic component. He argued that these disorders
are polygenetically inherited, share a number of genes in common that affect
dopamine, serotonin, and other neurotransmitters and are transmitted from
both parents. Implications of this hypothesis in relation to diagnosis
and treatment are reviewed, including the possibility that the genes involved
may be increasing in frequency.
In their article discussing possible pathogenesis
of Tourette's syndrome, Leckman, Peterson, Pauls, and Cohen (1997), also
explore genetic factors based primarily upon twin and familial studies.
The concordance rate was established and compared with the prevalence for
the general population. Neurobiology and the interrelatedness of
the basal ganglia, the cortical and thalamic structures to Tourette's syndrome
were hypothesized. Based upon studies of the basal ganglia, interest in
the neurochemical and neuropharmacological data related to Tourette's has
been pursued. These pursuits have focused on the dopaminergic, noradrenergic,
and serotonergic systems and the possible interconnectedness to Tourette's
syndrome. Also examined were gender-specific endocrine factors that
may be present with this disorder. The male/female ratio tends to
support this hypothesis. Considered, as well, were prenatal and perinatal
factors, including maternal stress during pregnancy, severe nausea or vomiting
in the first trimester, and low birth weight. Psychological factors
explored were related to the waxing and waning characteristics of the disorder
and the possible causes of such.
Eapen, O'Neill, Gurling, and Robertson's (1997)
article reported on their empirical study examining the possibility of
genomic imprinting as an influence on the phenotypic expression of TD.
Genomic imprinting refers to the differential expression of genetic material
depending on whether it has been transmitted maternally or paternally.
The researchers reported a significant difference in the age of onset,
with maternally transmitted TD showing up an earlier age. The authors
suggest that this indicated the possible impact of meiotic events (i.e.,
cell-splitting) or intrauterine influences. They argued that future
studies need to examine the family data separately for maternally and paternally
transmitted cases and suggested past conclusions that TD was transmitted
through a dominant autosomal pattern may have been premature. (In
a dominant autosomal pattern, there is a 50-50 chance for the offspring
to receive the genetic vulnerability when one parent is a carrier for the
gene.)
Psychological/Social/Cultural Influences
Leckman & Cohen's (1999) article presents
an integrated conceptualization of the etiology of TD based on current
research. The authors propose a model of interacting components that
include genetic factors (e.g., TD vulnerability genes), environmental and
epigenetic factors (e.g., prenatal risk factors, exposure to infections
or toxins, stress-related family, peer and social factors), and neurobiological
substrates (e.g., specific neurotransmitters and neuromodulators) that
act on and are acted on by each other over time to produce a phenotypic
expression of Tourette's syndrome.
In discussing the relevance of Tourette's
Syndrome and Tics for school psychologists, David Wodrich (1998) references
research that confirms that TD (or TS as he labels it) is mainly a genetic
disorder. Referencing Comings (1995) and others, Wodrich points to
biomedical factors such as birth weight and prenatal circulation as possible
influences on the expression of TD among people who are genetically predisposed.
Kurlan (1999) discusses the evidence for and
against the PANDA (pediatric autoimmune neuropsychiatric disorder after
streptococcal infection) theory of TD. He argues that since stress
or illness has already been shown to worsen tics, it may not be the specific
virus that triggers the onset of TD but rather the stress from the illness
itself. The author also suggests that even if TD was the result of
an infection, it is only true for a small portion of TD patients.
He discusses the important implication of this theory in terms of prevention
and treatment and states that more research is necessary before immunization
and testing for antibodies in recently diagnosed TD patients can be applied
routinely.
Spencer and colleagues' (1998) study proposed
to identify the similarities and differences in neuropsychiatric correlates
in children with TD and those with ADHD. Children with both TD and ADHD
were compared to children with TD alone or ADHD alone in terms of age of
onset, impairment, rates of mood, disruptive, anxiety, elimination, and
psychotic disorders, and rates of school dysfunction. Their results
show that, aside from OCD, rates of other comorbidities with disruptive
mood, behavior, and anxiety disorders were indistinguishable in comparison
between children with both TD and ADHD and children with ADHD alone.
The authors suggest that this may indicate that the many cognitive and
psychiatric impairments usually associated with TD could be secondary to
the comorbidity with ADHD, since ADHD is also a common comorbid condition
of TD. The findings also indicate that children with TD plus ADHD
have lower psychosocial function than children with ADHD alone.
Bawden and colleagues' (1998) study examining
peer relationship problems in children with TD questioned the influence
of a chronic illness on social problems. They compared children diagnosed
with TD with children suffering from another chronic illness (diabetes
mellitus) in order to determine whether the poor social adjustment often
noted among those with TD were a result of the generic affect of having
a chronic illness. Their results showed that children with TD had
poorer peer relationships than their classmates and this difficulty was
not related to the severity or duration of their tics. This finding
has implications for treatment since most efforts have focused on reducing
the severity and frequency of tics. Additionally, compared to the
children with diabetes, children with TD had poorer peer relationships
and were more likely to have extreme scores reflecting risk for peer relationship
problems, indicating that the presence of a chronic illness alone was not
enough to account for the social difficulties.
Staley, Wand, and Shady's (1997) article examines
the role that culture may play in the expression of TD. They searched
cross-cultural case reports, clinical investigations and epidemiological
studies in order to compare the characteristics of TD across different
cultures. The descriptions of cross-cultural cases of TD were similar
to those reported in the US in terms of average age of onset, the larger
ratio of boys affected compared to girls, and clinical features (e.g.,
the most common clinical feature was vocal tics). Interestingly,
in cases when coprolalia (a complex vocal tic in which inappropriate, often
obscene, words are uttered) was noted in cases found in Chinese and Arabic
cultures, the utterances were equivalents of western obscenities concerning
sex and body functions. The largest differences found was in the
occurrence and expression of coprolalia, with rates varying from
4-11% in Japan to 60% in Hong Kong. The authors commented that this
may be due to differences in diagnostic criteria, with some erroneously
thinking that coprolalia was necessary for a diagnosis of TD. The
comorbidity of certain psychiatric disorders such as OCD and ADHD were
also found across cultures. Treatment methods and success rate across
cultures were similar as well, indicating that the phenomenon being described
shared a common biologic basis to TD independent of culture or geography.
II. A DEVELOPMENTAL APPROACH
The developmental approach emphasizes the need
to examine a variety of factors, within, outside and surrounding the individual,
over time, in order to obtain a clearer conceptualization of a disorder.
In terms of etiology, this perspective draws on the medical, psychological,
sociocultural, and behavioral models to explain the underlying causes of
a disorder, believing that no one model can adequately explain such complex
phenomena like Tourette's disorder. As discussed in the Leckman,
King, Scahill, Findley, Ort, and Cohen chapter, Tics and other disorders
that impact a person's sense of well-being are only part of a larger story.
Children and adults with TD have to navigate through a myriad of vulnerabilities,
histories, and circumstances. In the introduction to this chapter,
Cohen, Detlor, Shaywitz, and Leckman (1982) captured the essence of the
developmental approach as it relates to TD when they wrote, "Tourette's
syndrome illuminates the need to see the child as a growing, differentiating
whole person, a psychosomatic entity, living in the complex environment
of home and family, not just the bearer of symptoms in need of elimination."
Although most of the research on TD has focused
on the genetics and neurophysiological factors, it is clear that such explanations
are incomplete without considering the influence and interaction of environmental
and intrapsychic factors. The findings that stress within the family
and/or from peers or educational settings affect the instance and duration
and intensity of tics, the possible influence of the intrauterine environment
and results from studies examining the possible role viral infections may
have in triggering certain cases of TD all suggest that the role of the
environment is not unimportant. This concept is illustrated
in Leckman and Cohen's (1999) chapter on their evolving model of pathogenesis.
From examining 25 years of research in this area, they present a dynamic
model that includes the interconnectedness and interactions of genetic
factors, neurobiological substrates and psychological characteristics.
Although the goal of much of the research seems to be to simplify and reduce
to gain a simple answer, it becomes clear that the picture only becomes
more complex and complicated as we continue to learn more about this disorder.
III. CONCLUSION
Although psychodynamic and neurophysiological
explanations for the etiology of Tourette's disorder have competed historically
(see Kushner, 1999 for an extended history), current conceptualizations
have embraced a more developmental approach. Leckman and Cohen's
(1999) model of the etiology of TD takes into consideration genetic, neurological,
and epigenetic or environmental factors. Twin and family studies
which are often used to illustrate the strong hereditary component of TD
also point out the importance of environmental factors since only 50% of
monozygotic twins (i.e., genetically identical) are both diagnosed with
TD (Hyde & Weinberger, 1995). Differences in severity and symptoms
among twins point to the importance of examining environmental and gene-environment
interaction factors. Combining the biomedical approach, which has
provided much information regarding the identification of the disorder
and other such biomedical information, with the developmental approach,
there is an opportunity to focus on the strengths of the individual with
TD rather than what is wrong with the person ("deficit model").
Despite the large amount of research already
conducted, there is still more to be done. For example, the exact
location(s) of the genes that cause the vulnerability to TD is yet to be
found. Additionally, more research is necessary to support the contention
that TD and OCD share the same genetic etiology. Also, as more is
learned about the neurobiology and genetics of TD, it is necessary to explore
in more detail the epigenetic effects which may account for the twins who
do not share their genetically identical sibling's disorder, or the cases
of TD that appear in families without a family history of the disorder,
or the factors that are related to the severity of tics, since the Lichter,
Dmochowski, Jackson, & Trinidad (1999) article suggests that tic severity
is not related to genetic dosage effects (i.e., the number of family members
with related conditions). The large number of variables that may
be involved in the etiology of this disorder points to the need for future
researchers to explore multifactorial explanations for the onset of TD
since the answer cannot lie in an entirely biological or entirely psychological/social
arena. These efforts to determine the underlying causes of TD can
ultimately be used to refine treatment for the care of children and adults
with this disorder as well as aid in diagnosis and classification.
I. ASSESSMENT
Assessment of Tourette's disorder can be difficult
because of the complexity of the disorder and the lack of standardized
measures. Additionally, although tics are very distinctive, the relative
rarity and unfamiliarity of the disorder may result in physicians and clinicians
missing or misdiagnosing tics and symptoms of Tourette's disorder as allergies,
ENT disorders, eye problems or even asthma (e.g., Hogan & Wilson, 1999).
The waxing and waning nature of tics and the ability of patients to suppress
tics to some extent add to the difficulty of assessment through direct
observation. As the patient becomes more comfortable with the doctor, there
is a possibility for the decreased likelihood of symptom suppression or
inhibition. When the patient becomes more comfortable with the child and
or has gotten used to the assessment practices, the child may feel freer
to express the tics more readily without suppression. In their 1994 article
Nolan et al., discussed some of the difficulties of assessment of Tourette’s
disorder. They suggested that the difficulties could stem from the
fact that the topography, frequency, and intensity of tics vary among and
within patients. Another difficulty that Nolan et al., point out
is the possibility that the fluctuation of the tic frequency may be task-specific.
The presence of an activity requiring greater concentration may reduce
the presence of tic in some and increase it in others. Because of
the inconsistent nature of the tics, traditional office visits and relying
on self and parental reports may not be sufficient for the assessment of
Tourette’s disorder.
Another factor contributing to the difficulty of
assessment is in the assumptions often made by clinicians and their lack
of understanding of the diagnostic criteria. One such assumption is that
coprolalia (i.e., use of inappropriate, often obscene, words and phrases)
is necessary for a diagnosis of Tourette's, the mistaken belief that motor
and vocal tics must be present simultaneously, and the misunderstanding
that tics may be volitional because patients can suppress them to some
extent.
Aside from the difficulties in observing and
rating the severity and chronicity of tics, a thorough evaluation also
needs to address the commonly associated co-morbid conditions, such as
ADHD, OCD, impulsivity, mood lability, and the child's family, school,
and social functioning. To date, there is no one instrument that
addresses all of these concerns.
Assessment strategies employed include clinical
interviews, clinician-rated instruments, videotaped observations, parent
and self-reports from the children, and neurological examinations to eliminate
alternative possibilities. Each category of assessments has specific instruments
which vary in their validity, reliability, and practicality. The results
of the neurologic exam of children with Tourette's does not provide definitive
proof for a diagnosis, but rather allows the clinician to rule out other
possible disorders that may present similar symptoms. When videotaped sessions
are rated, the clinician must keep in mind that children with this syndrome
have the ability to suppress some of the symptoms for periods of time.
Thus, the videotaping should be conducted in a variety of settings and
over a significant length of time. The clinical interview of the family
should include questions about the family history of Tourette's disorder
and other related behaviors, such as obsessions and compulsions and other
tic disorders.
The following literature review outlines issues in the assessment of
Tourette's Disorder. They attempt to provide a summary of and offer
information on the assessment instruments currently being used by both
researchers and clinicians.
Reviews of Assessment Procedures and Instruments:
Although it appeared nearly a decade ago, Leckman,
Towb, Ort, & Cohen's (1988) chapter on the clinical assessment of Tourette's
and other tic disorders is valuable because it outlines the difficulties
of assessment as well as compares the value of the different methods available.
Also of value is their description of the pros and cons of commonly used
instruments such as the Tourette Syndrome Severity Scale (TSSS; Walkup,
Rosenberg, Brown, & Singer, 1992), and the attachment of these instruments
in the appendix. Instruments appended include the Yale Global Tic
Severity Scale (Leckman et al, 1989), the Shapiro Tourette's Syndrome Severity
Scale (STSSS; Shapiro, Shapiro, Young, & Feinberg, 1988), and the Tourette's
Syndrome Global Scale (TSGS; Harcherick et al., 1984).
Sallee & Spratt's (1998) chapter on tics
and Tourette's provides an in-depth coverage of the possible assessment
strategies available for the determination of a Tourette's Syndrome diagnosis.
It delineates the various methods and means by which to perform an assessment.
The clinical interview is discussed and the authors point out the importance
of obtaining information in many different areas of functioning that may
be affected by the tics. The clinician is reminded to assess for
possible school, social and family impairment. This chapter offers
a comprehensive review of various instruments.
Walter & Carter's (1997) article offering
suggestions for school professionals explores the multi-dimensional aspect
of the assessment of Tourette's Syndrome and provides the rationale guiding
the diagnosis of this disorder. The authors describe what information needs
to be obtained regarding the child's background history. In addition, the
article encourages diagnosticians to beware of the variation in symptomatology
throughout the span of the child's day and life. The authors provide several
sources in which instruments can be obtained in order to assess children
who may have this disorder. The article encourages observations in a variety
of settings and by a multitude of individuals, including the clinician,
parents, child, teachers, and school psychologists.
Leckman, Peterson, Pauls, & Cohen (1997)
caution diagnosticians regarding disorders that may display similar symptoms,
thus a rather in-depth section discussing differential diagnosis is provided.
Several of the inventories to assess this disorder are also considered.
Various methods, including standardized videotaping of the child, are reported.
The article discusses the goals of assessment and dimensions that need
to be included. The necessity of exploring medication history, as well
as developmental history, is also examined.
Clinical Interviews
Robertson & Eapen (1996) argue that the
current instruments available are useful for assessment of the severity
of tics for research purposes, but they were not designed for overall assessment
of Tourette's Disorder and related symptoms. Additionally, many of
the instruments only cover a short period of time (e.g., the week prior
to assessment) and are time-consuming and unwieldy to use in a clinical
setting (e.g., Yale Global Tic Severity Scale; Leckman et al., 1989).
The authors designed the National Hospital Interview Schedule (NHIS) to
address these issues and offer an instrument that is quicker to administer
than the Yale (1 hour vs. 3 hours for a trained clinician) and could be
used in both research and clinical settings.
The NHIS is a semi-structured interview that provides an assessment
of the core symptoms of Tourette's as well as related behaviors, such as
obsessive-compulsive behaviors, self-injurious behaviors, and attention
deficit hyperactivity disorder. The instrument also covers information
on family functioning and the presence of Tourette's and related behaviors
in other family members. The authors offer information on their study
to establish the reliability and validity of their instrument. Their
results show that the NHIS has good inter-rater reliability and comparisons
with results obtained independently from the Yale Global Tic Severity Scale
resulted in strong correlations among scores, indicating concurrent validity.
The authors include both the NHIS and the Yale in their appendix.
Self-Report Assessments
Gaffney, Sieg, & Hellings (1994) developed a self-report scale for assessing the symptoms of Tourette's disorder. Named MOVES (or The Motor tic, Obsession and compulsion, and Vocal tic Evaluation Survey), the authors created the scale to be easily completed by children, adolescents, or adults. The instrument provides scores on 5 subscales: motor tics, vocal tics, obsessions, compulsions, and associated symptoms. Their empirical study examining the responses of 30 participants diagnosed with Tourette's Disorder showed that they scored significantly higher on the total scale and the subscales compared to 26 nonreferred community controls and 23 psychiatric controls. The authors reported significant correlation with independent clinician-rated scales such as the Yale Tourette's Syndrome Global Severity Scale and the Shapiro Tourette Clinical Rating Scale. Although more research is necessary, initial results seem to indicate that this instrument may be useful in monitoring clinical change and in separating Tourette's subjects from psychiatric and normal controls. An asset of this scale appears to be the inclusion of the obsessions and compulsion items in addition to items related to tics.
II. DEVELOPMENTAL PERSPECTIVE
An examination of the assessments created to
address Tourette's Disorder shows a focus almost solely on measuring the
number, type, severity and chronicity of tics. Although important
to assess the nature of tics, Tourette's is a disorder that can affect
several areas of functioning in a child's life and the disruptions to these
areas need to be addressed as well. As Peterson & Cohen
(1998) note, tic severity alone is not a good indication of current functioning
nor is it a good predictor of future functioning. A thorough assessment
needs to include an evaluation of the child's school functioning, family
life, peer relations, coping ability and the possible presence of comorbid
conditions such as OCD or ADHD. It is only with a conceptualization
from such an assessment that the appropriate treatment can be planned and
implemented. Additionally, assessment should continue even after
diagnosis in order to track the effectiveness of treatment and to record
the course of the disorder.
The most recent conceptualization of the etiology of Tourette's disorder
favors a multifactorial, transactional model which includes genetic, neurophysiological,
and environmental factors (Leckman & Cohen, 1999). It is hypothesized
that these factors interact and act on each other over time to result in
the various expressions of Tourette's and affects the course and the maintenance
of the disorder. With such a conceptualization, it becomes very clear
that a thorough assessment needs to include information about both genetic/biological
factors as well as environmental factors in order to have a more comprehensive
understanding of the effects these variables have on each other.
III. OPTIMAL ASSESSMENT STRATEGY
Based on the information presented earlier,
the optimal assessment strategy utilizes diverse information sources as
well as data gather techniques. As addressed earlier, there
are many factors that contribute to a child presenting with Tourette’s
disorder. To rule out any one particular factor may lead to a misdiagnosis
and/or an inappropriate course of treatment. Because Tourette’s disorder
is one that presents itself in a visual manner, direct patient observation
should be utilized by the clinician. The clinical observations should
not be viewed in isolation due to the inconsistency of the presence of
the tics. Because of this, it is also necessary for the child and/or
parent to provide information on the presence of the tics as they have
the opportunity to observe/experience firsthand. This is important
because during the time that the child is being observed, they may be no
visible displays of tics. Reports from the child and those who see the
child in various settings, i.e. parents/caretakers, siblings, and teachers.
However, as Leckman and colleagues (1988) note, the reliability of such
information is questionable due to their (probably) limited knowledge of
Tourette's and their lack of experience in making valid severity estimates.
The impact of this on the assessment may be limited by structuring the
interview and asking for concrete information.
In addition to observation by the clinician, a structured interview
is also recommended. Although the Yale Global Tic Severity Scale
(Leckman et al., 1989) provides a good overall assessment of Tourette's
symptoms as well as other related behaviors such as obsessions and compulsions,
it is time-consuming. A better choice may be the National Hospital
Interview Schedule (NHIS; Robertson & Eapen, 1996) which covers the
same areas but can be completed in a third of the time. This instrument
has the advantage of giving a global score of the core Tourette's symptoms
as well as information about related behaviors, such as ADHD. Items
in this instrument also gather information about the family history of
Tourette's, other tic disorders or other related conditions. Although
a newer instrument, an initial study indicates that the information gathered
from this tool is comparable to the information resulting from the widely
used and already validated Yale Scale (Robertson & Eapen, 1996).
However, the items would need to be modified depending on the age of the
patient as some of the questions are complex: a parent or a caretaker
may need to answer some of the items.
As mentioned previously, Tourette's disorder
is associated with several serious co-morbid conditions. Although
the NHIS addresses some of these concerns with its items concerning obsessions
and compulsions and ADHD behaviors, a more thorough evaluation may be warranted
after interviewing the family and child. Other scales such as the
Achenbach Child Behavioral Checklist (which has teacher, parent and child
versions) or the Connor's Parent Questionnaire may be useful in addressing
other issues, such as ADHD. To further assess obsessions and compulsions,
the Leyton Obsessional Inventory-child version-may be helpful.
Finally, the child might be referred to a
physician or neurologist to rule out other movement disorders that may
have similar symptoms to Tourette's, such as Sydenham's chorea, myoclonus
(brief muscle contractions), or dystonia (slow twisting movements as in
Huntington's disease). However, Tourette's can usually be differentiated
from these other disorders because tics are characteristically abrupt,
suppressible, and influenced by the influence of stress or relaxation.
IV. CONCLUSION
Assessing Tourette's disorder requires more
than merely counting tics. Because of the other serious comorbid
disorders that are often associated with Tourette's and because the symptoms
can impact many different domains of a child's life, a more global and
multifactored approach to assessment should be taken. In addition
to obtaining information about the nature of the child's tics, the clinician
needs to also gather information about family functioning, associated comorbid
behaviors (e.g., obsessions, compulsions, attentional problems), pre-morbid
functioning, coping skills (of both the family and the child) and the social
support available to the child and family. Only then can the clinician
begin to plan treatment interventions that will specifically address the
needs of the client.
Taking these considerations into account,
the optimal assessment should include direct observations by the clinician
or physician and interviews with the child, parent/caretaker, teacher and
other's closely associated with the child using a semi-structured interview
such as the NHIS. Information about family history and functioning
of the child in different settings also needs to be gathered in order to
determine whether other assessments (such as the Achenbach Child Behavior
Checklist or Leyton Obessional Inventory) are warranted. When considering
assessment of Tourette’s disorder, multiple factors need to be considered.
Because of the many variables associated with assessment, clinicians and
physicians need to be flexible in their approach and current in their practices
and knowledge.
I. TREATMENT
Although discussion of the treatment of Tourette's
Disorder often focuses on the reduction or elimination of tics, the first
job of the clinician is to educate and reassure the child and family about
the disorder. Peterson and Cohen (1998) propose that education is
the "single most important treatment modality" in the treatment of Tourette's
because of the hope and understanding that it provides and because it allows
the family to make educated decisions about treatment options. Because
Tourette's is seen as a neurological disorder, most think that the only
treatment option available is a pharmacological one. This is not
necessarily the case and some argue that medication should only be considered
when the tics are the main source of interference in the child's daily
life and development (e.g., Peterson & Cohen, 1998; Scahill et al,
1993). This is especially salient since no medication has been found
to completely eliminate tics and few empirical studies have examined the
effects of drugs on children.
Traditionally, neuroleptics (drugs that block
dopamine receptors in the brain) such as haloperidol and pimozide have
been prescribed. However, the serious negative side effects associated
with these drugs have led the search for alternative medications.
Currently, the drug first prescribed is clonidine because of the fewer
side effects associated with the drug. Unfortunately, clonidine is
not as effective as haloperidol in reducing tics. Other alternatives
to these drugs are tricyclic antidepressants, selective serotonin reuptake
inhibitors (SSRIs, such as Prozac), nicotine, and androgen blockers.
So far, none of the alternatives have been found to be as effective as
the neuroleptics in reducing tics (see Carpenter et al, 1999, for a thorough
review).
As with other chronic disorders, effective
treatment needs to move beyond the condition itself and also address the
child's and family's response to the disorder. Skillful and complete
assessment is necessary to determine the actual source of impairment since
tic severity itself is not a good indicator of current functioning or future
adaptation. Assessment may indicate that medication is not warranted
or that other modalities are necessary to address the specific difficulties
of a particular case. Alternatives and possible supplements to drug
treatment include family therapy, support groups, behavioral therapy, cognitive
therapy, and school interventions. Family therapy can be recommended
in order deal with the possible stressful reaction of the family that can
result in an exacerbation of tic symptoms. Because the tics associated
with Tourette’s can threaten the child’s self esteem, relationships and
interactions with others can be jeopardized in the process. Behavior therapy
involves habit reversals, progressive relaxation, self-monitoring of symptoms,
massed practice, and mental imagery and may help the child feel more in
control of his or her situation. While few empirical studies have tested
the efficacy of these treatment modalities, they have had various degrees
of success. One of the barriers to the documented efficacy of these
treatments is the fact that the subjects included individuals who were
poorly diagnosed to begin with and did not meet the diagnostic criteria
for Tourette’s. The use of a combination of treatments that had not
been tested individually is another area that led to the lack of validity
in the treatment options (King et al.,1999).
When comorbid conditions such as obsessive-compulsive
disorder or ADHD are also present, treatment becomes more complicated.
In terms of pharmacological interventions, the type of medication prescribed
differs according to the symptoms targeted (i.e., are obsessions, hyperactivity,
or tics the main reason for interference in daily life?). Additionally,
non-pharmacological interventions will probably also be necessary to address
possible learning problems, distractibility or hyperactivity, social problems
or issues with self-esteem and peer relations.
The following review of articles outlines
the recent research and conceptualization in the area of treatment.
They are divided into pharmacological treatments, psychotherapeutic interventions,
and multimodal models.
Pharmacological and Medical Interventions
Recently, Carpenter, Leckman, Scahill &
McDougal (1999) provided a review of pharmacological treatment over the
past 20 years and highlighted potential new interventions. They note
that, although the ideal medication that safely and effectively treats
tics has not been found, there has been progress in this field. The
authors report that medications protocol formulations are based upon what
the most difficult symptoms are. Short-term help can be provided but there
is not much data showing safety over time. When Tourette's is comorbid
with ADHD or OCD, the situation can be worsened by drugs normally used
to treat just one disorder. Thus far, there is not much empirical data
on combination treatments, and so these are not usually used. More research
is required to find better medications with lessened comorbidity incompatibility.
Pharmacotherapy targets certain features of Tourette's. The waxing and
waning aspect of Tourette's needs to be considered when giving medications.
The authors suggest a conservative model which includes a review of the
history to establish a solid baseline in order to determine whether to
medicate and to evaluate the effectiveness of treatment. The YGTSS is recommended
for monitoring response to any intervention.
Anti-dopaminergic agents (e.g., neuroleptics such as haloperidol
and pimozide) and alpha-adrenergic receptor agonists (e.g., clonidine)
constitute the main-stay of monotherapy for tic disorders without significant
comorbidity. Alternative drugs and combination therapies are reserved for
more complex cases. Atypical neuroleptic agents are commented upon as possible
alternatives to the drugs currently used. The authors describe the
function or mechanism of commonly prescribed drugs such as clonidine, guanfacine,
haloperidol, pimozide, risperidone, and clozapine, noting various good
and bad aspects and effectiveness rates. They discuss effects on the brain
and make some evaluation of the previously mentioned drugs as to their
relative efficacy with Tourette's and other associated disorders. Dosage
and protocol are outlined. Neurological interventions with surgery are
not recommended due to poor outcomes.
Murray (1997) explores the history of the
disorder, the lack of knowledge regarding the cause, and the profile of
those with the disorder. The article discusses current treatment techniques
of the initial pharmacological intervention of haloperidol. Nicotine and
cannabinoids are explored as possible options in the treatment arena, when
combined with neuroleptics. The possible side-effects are examined with
respect to the administration of haloperidol and the termination of such
treatments. Additionally, a D2 blocking medication, pimozide, was discussed
as a possible alternative to haloperidol with fewer side effects. Clonidine
as an effective alternative pharmacological intervention was proposed for
those having adverse reactions to
haloperidol.
In regards to alternatives to neuroleptics
and other traditional drugs, the results from Awaad's (1999) empirical
study of the effects of baclofen/botolinum toxin type A on tic symptoms
offers a potential new drug for the treatment of tics. In their study,
450 participants, aged 6-18 years, were treated with the baclofen/botolinum
toxin, which prevents the release of acetylcholine. Using the Yale
Global Tic Severity Scale and a videotaped analysis of tics, the researchers
found a significant reduction of tics without the considerable side effects
of the traditional drugs. Limitations to the study include the lack
of a placebo, control group and the fact that the study was not double-blind.
Although more studies are necessary to replicate the results, this study
offers a promising alternative to the current pharmacological treatments
offered.
Another possible alternative was tested by
Peterson, Zhang, Anderson, and Leckman (1998). The researches tested
the effects of an androgen receptor blocker (flutamide) in a double-blind,
placebo-controlled, cross-over trial involving ten men and three women
over a three week period. Side effects of the drug were few, but
only produced a significant reduction in motor and not phonic tic symptom
severity. Additionally, it modestly improved symptoms of obsessive-compulsive
disorder in the men who also had this disorder.
Castellenos and colleagues' (1998) report
on their empirical study is important in that it is one of the few controlled
drug trials that used children as participants (most other drug studies
have used adult subjects). The authors examined the effects of two
of the most commonly prescribed stimulants for comorbid ADHD and Tourette's
Disorder (methylphenidate and dextroamphetamine). The study used
a placebo-controlled, double-blind crossover design with three dosage levels.
Twenty boys between the ages of six and thirteen years participated in
the study. Results showed that, while a majority of the subjects
experienced an improvement in ADHD symptoms with acceptable effects on
tics, a substantial minority had constant worsening of tics. The
authors suggest that these drugs, especially methylphenidate which was
better tolerated, could be offered as viable treatment for children with
comorbid Tourette's and ADHD although parents should be advised that the
empirical data for such a decision remains few.
In a 1999 article by Bagheri et al., they
stated that the therapeutic goal in tic control should be the use of the
lowest dosage of medication that will enhance the person’s functioning
to an acceptable level. The neuroleptic drugs that the authors state
are the most commonly used are haloperidol, pimozide, risperidone, clonidine,
and guanfacine (which is not labeled for use with children under the age
of 12). These drugs are said to be modestly effective in tic
control. The drug that the authors indicate are the most effective
are the dopamine D@ antagonist drugs, but they also indicate that they
have the greatest side effects. The effects listed include sedation,
weight gain, impaired academic performance, and social anxiety. According
to Bagheri et al., most patients with Tourette’s require medication for
up to two years and 15 percent of patients require long-term medication
for tic control. The authors recommend a slow and gradual reduction of
medication when the tics appear to be stable and adequately controlled
for a period of four to six months.
In the 1999 article by Sheppard et al. They
discussed research that has been done for severe cases of Tourette’s in
which surgery was utilized. A bilateral limbic leucotomy was used
to decrease tic behavior and eliminate destructive behavior in a patient
who had failed to respond to drug therapy and who suffered from self-injurious
behavior. The authors state that treatments such as this are used
for only very severe cases and there remains to be seen whether this is
effective for milder tic cases.
Psychotherapeutic Interventions
King, Scahill, Findley, and Cohen's (1999)
chapter describes the subjective experience of Tourette's and other tic
disorders as productive of a "constant vigilance" to recognize and extinguish
the "urges" or "feel" of a particular tic expression "coming on." It describes
treatment as an intense training program. The chapter asserts that psychosocial
factors can help or hinder the waning of symptoms. Interpersonal and psychodynamic
interventions are said to deal with more development issues and developing
of more adaptive competencies. Pharmacological agents for reducing
tics should not be considered the end. Authors suggest utilizing exposure
and response interventions to deal with the OCD part of Tourette's. That
can help the patient to resist repetitions and reduce feelings of "incompleteness."
Habit reversal techniques and exposure-response
need more study. Behavior therapy and medications may work better than
medications alone. Massed-negative practice, contingency management, self-monitoring,
habit reversal-all suggested as helpful treatments. Outside of school or
regular settings, contingency management is not considered as helpful.
Empirical studies are discussed. Self-monitoring helped to reduce tics
when client was able to identify them. The best was composite habit reversal
procedures or simplified components. The latter part of the chapter discusses
common indications for psychotherapeutic interventions, including, low-self
esteem, impairing anxiety or depression and poor relationships, with families,
teachers, employers, and or peers. The authors cite facilitation of progress
as the goal for any psychodynamic interventions: progress in adaptive tasks,
relationships, friendships, acquiring mastery, and coherent positive identity.
Improving strategies can help decrease stress-produced tics as well as
medications levels. However, there are no empirical studies on this.
Lambert and Christie (1998) report on the
effectiveness of their social skills support group for boys with Tourette's.
Responding to parents concern over their children's apparent social isolation
and difficulty in making friends, the authors created a social skills support
group based on an existing protocol for use with children having specific
deficits in social interactions. The goals of Lambert and Christie's
(1998) seven-session program included raising self-esteem, improving communication
and interpersonal skills, increasing self-awareness and awareness of others,
and reducing the stress and anxiety associated with social interaction.
Interventions used to meet these goals included role-playing, practicing
conversation, learning to express and read emotions, and receiving feedback
from group leaders. Parents and children verbally reported improvements
in social skills and both parents and children reported beneficial effects
from the supportive interaction from meeting other parents and children
with Tourette's. However, the results of actual measures (e.g., Achenbach
Child Behavior Checklist, parent version) are unknown because few parents
returned the assessments. Further study is necessary for this promising
mode of intervention.
Multimodal Models
Leckman, King, Scahill, Findley, Ort, and Cohen
(1999) propose a holistic approach to treatment that addresses many areas
of functioning. They emphasize the need to focus on more than just
tic reduction for effective treatment. They begin by assessing familial,
school and social functioning of the individual and the accomplishments
of the child within those milieus. An important component to their
model includes examining the child's areas of strengths and resiliency
in addition to risk factors. Their approach to assessment and treatment
is holistic and multidisciplinary, utilizing neurological examinations
as well as pediatric, prenatal and birth histories. Four principles of
care are used in treatment planning: (1) educate the child, family, and
other involved professionals (teachers, physicians, etc.) about Tourette's
disorder and any related disorders; (2) given the chronicity of the disorder,
the assist the family in finding a long-term treatment setting; (3) emphasize
that the goal of treatment is to minimize the negative effects of Tourette's
on the child and family and to ensure the child's optimal development-the
goal is not the total eradication of tics (4) obtain a consensus from all
involved about which symptoms to target and how.
The chapter offers excellent tables on different
treatment options (e.g., supportive and education approaches, pharmacological
treatments, cognitive-behavioral treatments, support groups, etc.) and
describes circumstances when such interventions are warranted. The
authors emphasize that their most important principle is "optimizing adaptation
and keeping development on track." They comment that the constant
focus and over-emphasis on tics and assessing tic severity can amplify
the traumatic effects of Tourette's and obscure the many strengths and
abilities that the child already has. They argue that one of the
most important tasks for clinicians to do is to foster normal development
despite the challenges of Tourette's.
Peterson and Cohen's (1998) article also emphasized
the need to individualize treatment according to the specific needs of
the client. They argue that effective treatment needs to include
more than just tic reduction and they discuss both pharmacological interventions
that deal with tic symptoms as well as other interventions that target
co-morbid illnesses as well as coping strategies and support. They
state that education and support are necessary and important in almost
all cases of Tourette's. Other types of treatments explored are psychotherapies,
pharmacotherapies, and treatment of comorbid disorders. The psychotherapies
examined are mental imagery, habit reversal, and dynamic psychotherapies.
The article stated that "the most frequent intervention in TS is reassurance
and support."
Chappell, Scahill, and Leckman (1997) discussed
the limitations of current psychopharmacological therapies, such as intense
side-effects and limited efficacy. New pharmacological treatments were
examined, including atypical neuroleptic agents, such as clozapine, risperidone,
and D2 blockers. Antidopaminergic agents were also discussed, including
pergolide, talipexole, and tetrabenazine. Therapies for comorbid disorders
(such as ADHD and OCD) were also mentioned.
Additionally, the importance of monitoring
and modulating stress sensitivity in TS patients was examined. Additional
therapies for the treatment of TS were explored, including immunomodulatory
therapy, behavioral therapy, hormonal therapy, injections of botulinum
toxin, and neurosurgical interventions. Surprisingly, the immunomodulatory
therapy, which is based upon the supposition that certain "streptococcal
or viral infections may trigger autoimmune processes that cause or exacerbate
some cases of childhood-onset ...TS", suggests that there was a decrease
of up to 100% of tic severity in a patient. If these results could be replicated,
it would indeed be a major advance in the treatment of TS.
Coffey and Park's (1997) article emphasized
the behavioral phenomenology and specific behavioral and emotional features
associated with the disorder. It discussed the various comorbid disorders
that were often present, such as ADHD, OCD, mood and anxiety disorders,
psychotic illness, and self-injurious behavior. Diagnostic evaluation of
these features were explored. The treatment regimen that was explored was
with respect to the behavioral and emotional symptoms associated with Tourette's
Syndrome (TS).
The authors indicated the need to treat the
symptoms that were providing the most difficulty to the patient, in order
of impairment. Pharmacological interventions were examined for TS and the
accompanying comorbid disorders. A multimodal means of treatment was "recommended
for patients with clinically significant behavioral and emotional features".
Several modes of behavioral therapies were discussed, including relaxation
techniques and individual psychotherapy.
II. DEVELOPMENTAL PERSPECTIVE
Although much of the research in the treatment
of Tourette's focuses on the pharmacological agents that may alleviate
tic symptoms, a developmental view of the disorder requires a broader target
for intervention. As has been discussed, there are various approaches
to the treatment of Tourette’s and it is shortsighted to consider only
one as the absolute answer. From a developmental perspective, the
threatment of Tourette’s can be viewed as needing a multivariate approach.
Those ascribing to the developmental approach recognize the need to focus
on the entire patient with the disorder and not focus solely on the presentation
of tics. Tic symptoms are just one component that may need to be
addressed in the effective treatment of this disorder and in some cases,
medication need not be a component of treatment. From the developmental
perspective, other factors that affect the manifestation of symptoms and
the experience of the disorder, such as family environment, social isolation,
or learning problems, also need to be considered. Additionally, it
is important to note strengths and resiliency factors that may ameliorate
or help the child and family cope with the disorder. The effect that
the disorder has on the child's normal development must be taken into account
and assessed. It is only with an accurate and complete assessment
that the proper intervention can be undertaken. These issues have
only recently been considered in planning treatment for Tourette's disorder.
Just as the etiological model of this disorder has become more complex
and now examines the transactional nature of the interacting components
implicated, the conceptualization of treatment needs to follow suit and
begin to address variables in different arenas: medical, social,
familial, individual. Addressing these additional factors makes it
necessary for the clinician to look further than medical treatments.
Other types of interventions, such as family therapy, support groups, cognitive-behavioral
therapy for the individual, social skills training, or adjusting the school
environment to accommodate the needs of the individual, may be useful in
optimizing the ability of the child to keep on track developmentally.
III. OPTIMAL TREATMENT APPROACH
The optimal approach to treatment begins with
a careful and thorough assessment of the individual and his or her unique
case. It is not enough to just count tics or measure tic severity
because that would not provide an accurate picture of the client's needs.
Areas of dysfunction, possible comorbid conditions, psychosocial adjustment,
and areas of strength need to be assessed before a treatment plan can be
suggested. After assessment, a multi-modal, multi-disciplinary approach
is suggested. However, it must be kept in mind that assessment continues
throughout the implementation of treatment, especially if medication is
chosen as a modality.
Although Tourette's disorder is considered
primarily a neurological disorder, the influence of family environment,
individual coping ability, comorbid conditions and school functioning need
to be considered in implementing effective treatment because of their important
role in the development and maintenance of the disorder. Treatment
should be individualized to meet the specific psychosocial and medical
needs of the client. In all cases, the child, family, and other professionals
involved (e.g, pediatrician, teacher) should be educated about the disorder.
Additionally, supportive therapy should be offered to the family to help
them deal effectively with the diagnosis since a negative reaction to the
diagnosis of a chronic condition may exacerbate the situation.
The clinician needs to examine where the most
impairment is located and what the primary source of impairment is.
Medication should not be the first choice of treatment and should only
be used when tic symptoms are sufficiently severe as to interfere greatly
with daily functioning or to pose harm to the child (e.g., head-banging,
self-injurous behaviors). Cognitive behavioral treatments are suggested
for moderately severe tics and comorbid obsessive-compulsive symptoms,
anxiety, depression and ADHD symptoms. In cases where assessment
finds that the family's or individual's long-term adjustment to the disorder
is problematic, traditional psychotherapy or family therapy may be warranted.
To address possible school problems, help from the child's teacher and
school should be enlisted to adapt the classroom to accommodate any special
needs. The guiding principle of treatment should to be to treat the
child and not the disorder; the clinician should work to foster normal
development despite the challenges of Tourette's disorder. In light of
the pros and cons presented by the various treatment options, it is clear
that there is no “right” answer. As each patient is different the
course of treatment should be different as well. By addressing the
entire patient and allowing him/her to give insights, the clinician and/or
physician has a better chance of assisting the patient deal with the multifaceted
issues of Tourette’s disorder.
IV. CONCLUSION
In addition to tics, which may interfere with daily functioning, Tourette's disorder is often associated with other problematic symptoms such as hyperactivity, distractibility, obsessions, compulsions, depression and anxiety. This disorder is also associated with social isolation and rejection, stressful family environments, and school failure. It is therefore clear that treatment needs to be multimodal and multi-targeted instead of focusing solely on tic reduction. Unfortunately, empirical studies on the efficacy of interventions that focus on the psychosocial functioning of the Tourette's patient are rare. Despite this lack of empirical data, a multidimensional approach allows the clinician to be flexible and involves important people in the child's life, such as the parents, educators, physicians. This approach also allows the clinician personalize the treatment for the client's specific needs. As Howard Kushner (1999) stated, “As many researchers continue to learn, support for research into new and promising arenas requires more than scientific and medical skill. Given this reality, the best allies may be patients and their families. The afflicted have as much to tell us about their disease as researchers and clinicians have to tell one another”. This is a salient point in that it recognizes the need to explore various treatment options for individuals.
The following web sites about Tourette's Disorder deal specifically with treatment issues:
Tourette Syndrome Plus's Guide to Treatment
http://www.tourettesyndrome.net/treatment_tics.htm
Written by a clinician with many years treating children with Tourette's
and advocating for patients and families, this is an excellent site geared
towards parents, caregivers and educators. The author gives parents
a list of questions to ask physicians about medication and offers helpful
links to other sites (e.g., a site to check potential drug interactions).
The great site offers good information to parents on the conventional treatments
as well as the alternatives, citing recent research for support.
Additionally, the site offers a bibliography and a trade name-generic name
conversion table.
University of Iowa Description of Pediatric Psychopharmacology of Tourette's
Disorder
http://indy.radiology.uiowa.edu/Providers/Conferences/CPS/42.html
This web site seems especially suited for the medical professional.
It discusses the pediatric psychopharmacology of Tourette's Syndrome. The
efficacy, side effects, dosage, population, and results are discussed for
a number of various interventions for this disorder. This page cites empirical
studies and offers a bibliography. A very nice feature is a table
summarizing the results of the different studies mentioned on the site.
http://www-personal.umd.umich.edu/~infinit/tsfaq1.3.html
This site explores the cause and treatment of TS. This site seems most
appropriate for the family or individual that may be suffering from this
disorder. It provides treatment options available, but discusses the information
in a personal context. This site offers the view that medication is not
always necessary and should be considered only when the tics interfere
with daily life to a large extent. Additionally, author of the FAQ
consistently maintains a positive attitude about Tourette's and points
out potential strengths (e.g., the contention that those with Tourette's
are often very creative and think in original ways).
http://pages.prodigy.com/laura/treatmen.htm
This site is geared toward the families of those with this disorder.
It urges against the supposition of a "magic pill" that will eliminate
all of the symptomatology and provide instant relief from this syndrome.
It also discusses the possible side effects that may occur as a result
of the medication that is taken as a relief from TS symptoms.
Tourette Syndrome Association's Guide to the Treatment of Tourette's
http://www.mentalhealth.com/book/p40-gtor.html#Head_4
This site is written for the clinician or prescribing physician.
It outlines information on traditional drug treatments but also offers
suggestions for other interventions to address psychosocial problems.
Treatments discussed include family therapy, psychodynamic therapy, and
genetic counseling. Academic and occupational interventions are also
noted.
University of Iowa's Virtual Hospital: The Medical Treatment of
Tourette's
http://www.vh.org/Patients/IHB/Psych/Tourette/TSMed.html#9
Again, this site is written for physicians and offers a short summary
of conventional drug treatments for Tourette's, Tourette's comorbid with
OCD and Tourette's comorbid with ADHD. It mentions (briefly) environmental
factors associated with the exacerbation and lessening of symptoms and
lists factors that may result in problems at school. The authors
emphasize that the goal of treatment is to clarify the reasons for dysfunction
and to develop individualized, multi-modal treatment programs for the patient.
V. A FINAL WORD
Although Tourette's disorder is seen primarily
as a neurological disorder, it is clear from the previous discussion that
it is still best conceptualized using a developmental model. The experience
of Tourette's disorder is often associated with negative school outcome,
comorbid conditions of ADHD, OCD, and learning disabilities, and social
ostracism and rejection. Additionally, it is important for the clinician
to remember the significant contributions to the expression of the disorder
made by the child's individual coping ability, risk and resilience factors,
and his or her family, school and social environments. The clinican
can definitely play a role in helping the child and family deal with some
of the psychosocial factors associated with a diagnosis of Tourette's disorder
by providing support, education, and therapy to deal with behaviors associated
with possible comorbid conditions. The first line of defense need
not be medication.
Despite the recent surge in research on the
topic of Tourette's disorder, there is still much more to learn.
For example, epidemiological questions still exist and may be clarified
soon with the creation of better instrumentation, methodology, and recognition
of the disorder. Much has been done in the area of the biology and
genetics of Tourette's but the precise etiology is still unknown.
With more answers to the causes of Tourette's, treatment can be better
tailored to be more effective. Currently, no one ideal intervention
exists to eliminate tics entirely and few empirical studies have examined
the efficacy of non-pharmacological treatments that deal with the psychosocial
aspects of Tourette's disorder. Clinicians, with their experience
of using non-pharmacological interventions to deal with OCD, ADHD, and
other disorders, are in a good position to add to the research literature
in this sadly lacking area by creating more efficacy studies of non-drug
treatments.
VI. TOP TEN WORLD WIDE WEB SITES:
Tourette Syndrome Plus
http://www.tourettesyndrome.net
This excellent site is written to educate those with Tourette's and
their families; however, the very comprehensive coverage of information
can be useful to others as well, including clinicians, physicians and educators.
The author is a licensed psychologist who has worked as an advocate in
the Tourette's community for the last ten years. She provides essential
basic information (e.g., etiology, symptomology, treatment, assessment)
and focuses on comorbid issues such as ADHD, "rages," bipolar disorder,
and learning problems. A very nice feature of the site is a glossary
of biochemical, neurological and medical jargon usually found in the literature.
Additionally, the site offers guidance to parents on being better mental
health consumers and gives advice for advocating for their child.
The section on treatment is very comprehensive and demystifies the process
for parents.
Database of Tourette's Disorder Research
http://www.mentalhealth.com/fr20.html
This is the database of the most current research on TD that has been
published in refereed medical and psychiatric journals. The site
provides the navigator with an index of research topics regarding TD (e.g.,
etiology, education, psychotherapy, epidemiology, psychopharmacology) to
select from and then displays the abstracts of the chosen articles.
Instructions for ordering the articles are also provided (this must be
done through a local health science library).
Tourette Syndrome Association Website
http://tsa-usa.org
This is the website of the only national organization dedicated to
Tourette's disorder. This site explores the interaction between different
aspects of Tourette's Syndrome. It provides a well written description
of the disorder, as well as facts and myths concerning TS. The web location
discusses medical and scientific information, including publications, diagnosis
and treatment. The site also offers information on how to obtain a newsletter
for children with Tourette's written by children with Tourette's.
Recognition and Management of Tourette's Syndrome and Tic Disorders:
http://www.aafp.org/afp/990415ap/2263.html
A site designed for doctors, it offers a concise summary of the disorder,
including issues in assessment, such as differential diagnosis. Although
initially intended for physicians, a clinician would also find the site
helpful. Especially nice is a printable "Patient's Information Handout
on Tourette's" that offers useful and easy to understand information for
parents with a newly diagnosed child.
Tourette Syndrome Information:
http://www.wemove.org/ts.html
Created by WE MOVE, an organization with the goals of educating healthcare
professionals worldwide about movement disorders and their management,
facilitating the development of resources and educational materials about
movement disorders, and assisting healthcare professionals and patients
with establishing support groups around the world. This site provides
basic information about Tourette's and emphasizes the need for a thorough
clinical evaluation. A great feature of this site is that medical
terms and neuropsychological terms are defined (e.g., certain words are
highlighted and clicking on them will result in a box popping up on the
screen defining the term). A full glossary is also provided that
may be helpful to those not familiar with the technical terms used in medical
research.
Internet Mental Health's Guide to the Clinical Assessment of Tourette's
Disorder
http://www.mentalhealth.com/book/p40-gtor.html#Head_3
This site discusses the difficulties of diagnosing and assessing Tourette's
Disorder. Written for the clinician or physician, it discusses the
areas that a thorough assessment needs to cover (e.g., level of functioning
at home and school, possibilities of learning disabilities or attentional
problems, social, family, or peer problems, the importance of getting a
family history, etc.). The site also points out the need for the
clinician to be aware of possible secondary issues, such as the family's
response to the diagnosis which may require psychoeducation and/or supportive
therapy for the child and family.
Tourette Syndrome Plus's Guide to Treatment
http://www.tourettesyndrome.net/treatment_tics.htm
Written by a clinician with many years treating children with Tourette's
and advocating for patients and families, this is an excellent site geared
towards parents, caregivers and educators. The author gives parents
a list of questions to ask physicians about medication and offers helpful
links to other sites (e.g., a site to check potential drug interactions).
The great site offers good information to parents on the conventional treatments
as well as the alternatives, citing recent research for support.
Additionally, the site offers a bibliography and a trade name-generic name
conversion table.
University of Iowa Description of Pediatric Psychopharmacology of Tourette's
Disorder
http://www.vh.org/Providers/Conferences/CPS/42.html
This web site seems especially suited for the medical professional.
It discusses the pediatric psychopharmacology of Tourette's Syndrome. The
efficacy, side effects, dosage, population, and results are discussed for
a number of various interventions for this disorder. This page cites empirical
studies and offers a bibliography. A very nice feature is a table
summarizing the results of the different studies mentioned on the site.
Adults with Tourette Syndrome
http://www.ddonin.com
This site is intended for adults with the disorder. The site focuses
on the long-term effects of Tourette Syndrome on adults and highlights
accomplishments of adults with Tourette Syndrome. Another feature
of the site is that it offers links to other sites pertaining to Tourette
Syndrome. The "Issues and Opinions" section is a good resource for
those working with people with Tourette Syndrome because it gives an indication
of the kinds of things that these individuals struggle with every day.
National Institute of Neurological Disorders and Stroke (NINDS)
http:/www.ninds.nih.gov/health_and_medical/disorders/tourette.htm
This site is sponsored by the National Institute of Neurological Disorders
and Stroke. The goal of the NINDS is to support biomedical research
on disorders of the brain and nervous system. This site is useful
in that it gives a short synopsis of the various areas such as, definition,
treatment, prognosis, and current research. What is very helpful
is the "Tourette Syndrome Fact Sheet" that is part of the web site.
The Fact sheet is actually a 5 page guide that covers tics, disorders associated
with Tourette Syndrome, diagnosis, treatment, and information on the best
educational setting for children with Tourette Syndrome.
Tourette Syndrome and Associated Disorders
http:/expage.com/page/tobi1
This is a web page devoted to providing up to date web site information
on current web sites dealing with Tourette Syndrome. This web site
has a direct link to each site listed. All of the links are active
and provide a wide range of resource information. Some of the links
direct you to sites specific to geographic areas while others focus on
particular age groups. Some sites serve as support areas for people
with the disorder while others provide information from national research
and advocacy associations.
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