- A
Cursing Brain? The histories of Tourette
Syndrome. Kushner HI 1999
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- Tic
disorders are commonly considered to be
childhood syndromes. Childhood onset is a
defining feature of Tourette's
syndrome, a chronic disorder of severe motor
and vocal tics that begins before the age of 18
or 21 depending on the criteria. The childhood
onset of tic disorders has been consistently
described since Gilles de la Tourette's seminal
report, in which all eight patients presented
with tics during childhood. The DSM-IV
classification of tic disorders does not include
a category for tic disorders that develop during
adulthood, other than tic disorder "not
otherwise specified". Tic disorders experienced
during adulthood are largely considered to be
persistent ticsfrom childhood. In adults
presenting with atic disorder, it is often
assumed that the patients cannot remember having
experienced childhood tics. As such, tic
disorders newly presenting during adulthood have
only occasionally been described in isolated
case reports, and mostly in the context of
symptomatic, or secondary, tic disorders. The
goal of the present study was to describe a
large series of patients with tic disorders
presenting during adulthood, to compare
clinical characteristics between groups of
patients, and to call attention to this
potentially disabling and underrecognised
neurological disorder.
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- Case 12 : 46 year old man with
obsessivecompulsive disorder was referred by his
psychiatrist because of frequent yawning spells.
It soon became apparent that his movements,
superficially resembling yawning, were different
from his normal yawning. The yawning movements
were preceded by a sensation of drowning or
suffocation that could only be relieved if the
yawning movement was "just right: I need that
good breath". The yawning was temporarily
suppressible, and did not occur if the patient
was distracted. The yawning could be substituted
for by a sigh, which also abolished the
sensation of asphyxia. Diazepam helped to reduce
the movement. There was history of previous
tics, and the family history was notable for
Parkinson's disease. As a child, the patient had
obsessive rituals that did not impair
him.
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- Discussion
- Tic disorders newly presenting during
adulthood have occasionally been described in
the neurological literature, mostly in relation
to an acquired brain lesion, or as incidental
tics in the context of another neurological or
psychiatric disease, such as Huntington's
disease. There are few descriptions of primary,
or idiopathic, adult onset tics in the
literature, and about 55% of reported cases
represent recurrences of childhood tic
disorders,as shown in table 3.
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- The largest report is that of Klawans and
Barr, who described four patients with childhood
onset tics that remitted before the age of 21,
only to recur after the age of 60. Taken
together, the paucity of reports of adult onset
tic disorders suggests that they represent an
unusual entity, especially idiopathic tic
disorders, rarely encountered in clinical
practice, in marked contrast to the high
prevalence of childhood tic disorders.
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- The present series of 22 patients is the
largest report describing the clinical features
of tic disorders presenting during adulthood. In
our population, adults newly presenting with
tic disorders represent 5.4% of patients of all
ages evaluated for tics. We cannot estimate
the prevalence of adult onset tic disorders in
thegeneral population, but the number of
patients we have encountered suggests that the
phenomenon is more common than previously
reported.
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- When adults present for the first time to a
physician for evaluation of a tic disorder, a
certain number will have true new onset tics,
whereas the rest will prove to have a recurrence
of a childhood tic disorder. Among adults with
new onset tics, about 50% will have an apparent
external precipitant of the disorder.
Establishing that an adult patient with apparent
new onset tics did not have tics during
childhood can rarely be done with certainty
because some patients are unaware of their tics,
and reliable observers who knew the patient as a
child may not be available. As such, it is
important to divide adult onset tic disorders
into two categories based on the time course of
presentation: a new tic disorder after the age
of 21 years or the recurrence of childhood tics
that had previously resolved. In the present
series, the categorical breakdown among 22
patients was: idiopathic new onset tics in seven
(32%), new onset secondary tic disorder in six
(27%), and recurrent childhood tic disorder in
nine (41%).
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- The clinical features of adult onset tic
disorders resemble those described in childhood
onset tic disorders. However, the range of tic
phenomenology in our population seemed more
restricted relative to childhood tics, and the
severity of tic disorders was milder. There was
little coprolalia, as has been previously noted
in childhood tics persisting into adulthood.
Automatisms of the type described in autistic
children were not found in this sample, but may
reflect referral bias, as adults with autistic
behaviours are not generally referred to our
clinic. In our population, there were no
phenomenological dfferences between patients
with de novo adult onset tics and those patients
with recurrent childhood tics. Both groups
exhibited tics that most often involved the
face, neck, and shoulder.Most patients had
multiple motor tics.
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- In the series, only six patients had an
isolated single tic disorder, but three others
had a primary tic that overshadowed a background
of multiple, minor tics. Single tics and
dominant tics persisted over the full course of
the disorder, waxing and waning in severity but
not varying in repertoire. In both groups, no
patient had a complete remission of their tics
in adulthood. Treatment attempts were
generally not successful, and rarely
sustained. Eventually, most patients elected
to discontinue medical treatment, prefering to
live with their tics than to experience the side
ffects of medication.
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- The concept that obsessive-compulsive
disorder is part of the range of
neurobehavioral manifestations of Tourette's
syndrome is well accepted, and in our series was
present in nine of 22 patients (40.9%).
Disability was not formally quantified in our
population, and we could not distinguish
disability due to tics from disability caused by
attendant psychopathology.
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- In general, patients stated that they were
mainly socially disabled by their tics, in
agreement with studies describing social
embarrassment and isolation as the most
disabling consequences of tic disorders. All of
our patients were self referred for tics, a
referral bias that usually selects for more
severely ffected people. However, based on
interviewswith the patients and review of the
patients'videotaped neurological examinations,
the patients in this series would be considered
to haveonly mild (score 0 to 24) or moderate
(score 25 to 39) severity tic disorder, using a
standard rating scale. We did not encounter any
patient presenting during adulthood with a tic
disorder at the extreme end of the severity
range, with tics so disruptive and intractable
that social, familial, or occupational
functioning is all but precluded.
- All adults with this degree of disease
severity followed at our centre developed their
disorders during childhood.The prevalence of
symptomatic tic disorders seems significantly
higher among adults with new onset tic disorders
than for adults with recurrent childhood tics, a
finding inferred from the number of published
reports of secondary tic disorders in the
literature. Adults with new onset tics are also
more likely to have an underlying cause or
provocative event for their tics than children
with tic disorders.
- By contrast, childhood onset tic disorders
are only rarely linked to a specific aetiology.
Almost one third of the patients in this series
reported the onset of tics after a clear
inciting event, including neck strain, head
injury, local infection, cocaine binge usage,
and exposure to neuroleptic drugs, all
conditions known to precipitate tics. The
literature suggests that tics caused by
peripheral trauma tend to be single, non-varying
isolated tics, and the two patients in our
series who come closest to a peripheral physical
injury (cases 3 and 9) support this notion.
- The question arises as to whether those with
secondary tics would have gone on to develop
tics in the absence of the precipitating event.
In our cases of secondary tic disorders, and
among adult onset post-traumatic cases described
in the literature, about half had a history of
attention deficit hyperactivity disorder,
obsessive compulsive traits, or a family history
of tic disorder, or obsessive-compulsive
disorder, all biological substrates often linked
to primary, or idiopathic, tic disorders. The
true prevalence of adult onset tic disorders
remains unknown.
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- Simple observation suggests that tics in
adults may not be uncommon, but the phenomenon
has not been studied systematically. One
diffculty in obtaining an accurate prevalence
figure of adult tic disorders is that many
people with tics are unaware of their symptoms.
People may also be unaware of tics in family
members. Tics wax and wane, and are
suppressible, sometimes unconsciously, escaping
detection even by an expert in a standardised
setting. The frequency andintensity of tic
disorders decreases with time, making adult
cases of tics even more dffcult to ascertain.
All of these problems may lead to
underrecognition of tics, which in turn has
likely impeded the development of biological or
genetic markers for tic disorders. Do adult
onset tics constitute one end of the range of
Tourette's syndrome? In this series of 22
patients, it would seem that the phenomenology
of adult tic disorders, the clinical features,
prognosis, family history, and associated
neurobehavioural elements are entirely typical
of childhood onset tic disorders.
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- The clinical evidence suggests that adult
tic disorders are part of a range of illness
that includes childhood onset tics and
Tourette's syndrome. We therefore propose that
classifications of tic disorders include an
adult age category that is subdivided by disease
course into tic disorders that persist from
childhood, tic disorders that represent a
recurrence of transient childhood tics, and
genuine new onset adult tic disorders. Within
the category of adult onset tics, it also seems
important to dfferentiate primary from secondary
tic disorders, and most of the secondary cases
will fall into the new onset adult tic disorder
category. We anticipate that the classification
of tic disorders, now based entirely on clinical
criteria, will become clearer with the
development of genetic markers.
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