Tourette's disorder: epidemiology and comorbidity in primary school children

Tourette syndrome and tic disorders: a decade of progress

OBJECTIVE

This is a review of progress made in the understanding of Tourette syndrome (TS) during the past decade including models of pathogenesis, state-of-the-art assessment techniques, and treatment.

METHOD

Computerized literature searches were conducted under the key words "Tourette syndrome," "Tourette disorder," and "tics." Only references from 1996-2006 were included.

RESULTS

Studies have documented the natural history of TS and the finding that tics usually improve by the end of the second decade of life. It has also become clear that TS frequently co-occurs with attention-deficit/hyperactivity disorder), obsessive-compulsive disorder, and a range of other mood and anxiety disorders. These comorbid conditions are often the major source of impairment for the affected child. Advances have also been made in understanding the underlying neurobiology of TS using in vivo neuroimaging and neurophysiology techniques. Progress on the genetic front has been less rapid. Proper diagnosis and education (involving the affected child and his or her parents, teachers, and peers) are essential prerequisites to the successful management of children with TS. When necessary, modestly effective antitic medications are available, although intervening to treat the comorbid attention-deficit/hyperactivity disorder and/or obsessive-compulsive disorder is usually the place to start.

CONCLUSIONS

Prospective longitudinal studies and randomized clinical trials have led to the refinement of several models of pathogenesis and advanced our evidence base regarding treatment options. However, fully explanatory models are needed that would allow for more accurate prognosis and the development of targeted and efficacious treatments.

Developmental psychopathology of children and adolescents with Tourette syndrome--impact of ADHD

BACKGROUND

In Tourette syndrome (TS) as a neurodevelopmental disorder not only the tics but also the comorbid conditions change with increasing age. ADHD is highly comorbid with TS and usually impairs psychosocial functioning more than the tics. Its impact on further comorbidity during development is important for clinical practice and still a matter of debate.

METHOD

Aspects of developmental psychopathology considering the impact of ADHD were examined by logistic regression (year wisely) in a cross-sectional sample of children and adolescents (n = 5060) from the TIC database.

RESULTS

In TS+ADHD (compared to TS-ADHD) higher rates of comorbid conditions like OCD, anxiety disorders, CD/ODD and mood disorders were found in children (5-10 years). In adolescents (11-17 years) higher comorbidity rates in TS+ADHD remained only for CD/ODD and mood disorders. Accordingly, for OCD and anxiety disorders there was a steeper year wise increase of these comorbidities in TS-ADHD while it was a similar for CD/ODD and mood disorders in TS-ADHD as well as TS+ADHD.

CONCLUSION

Children with TS+ADHD have more comorbidities than the TS-ADHD group, whereas in both adolescent groups this did no longer hold for OCD and anxiety disorders. These findings indicate that in TS comorbid ADHD is associated with high rates of externalizing and internalizing problems, whereas TS without ADHD is associated only with internalizing problems in adolescence.

Clinical effectiveness of quetiapine in children and adolescents with Tourette's syndrome : a retrospective case-note survey

BACKGROUND AND OBJECTIVE

Tourette's syndrome is a relatively common biological genetic disorder with a broad spectrum of neurobehavioural manifestations. Unfortunately, treatment of the condition is often unsatisfactory and all available drugs are associated with potential adverse effects. We therefore aimed to investigate the efficacy of quetiapine, a newer atypical antipsychotic, in the treatment of children and adolescents with Tourette's syndrome.

METHODS

This was a retrospective study carried out in outpatient clinics. Twelve patients aged 8-18 years with Tourette's syndrome (diagnosed according to Diagnostic and Statistical Manual IV criteria) who were receiving quetiapine therapy and had no diagnosis of epilepsy, major depression or psychotic disorder, were included in the study. The main outcome measure was the Yale Global Tic Severity Scale (YGTSS) score.

RESULTS

The initial dose of quetiapine was 25 mg/day, but the mean dose was increased to 114.6 +/- 51.6 mg/day and 175.0 +/- 116.8 mg/day at the fourth and eighth weeks of treatment, respectively. The YGTSS score, which was 21.6 +/- 4.0 at baseline, showed significant decreases at 4 and 8 weeks (reducing to 7.5 +/- 7.4 and 5.6 +/- 8.1, respectively; p < 0.003). Routine laboratory parameters and serum prolactin level were all normal and did not change throughout treatment. Mild but significant increases in both bodyweight and body mass index at 4 and 8 weeks compared with baseline were observed.

CONCLUSION

Other than causing mild weight gain, quetiapine appears to be an effective, safe and well tolerated drug in children and adolescents with Tourette's syndrome.

Tic symptom profiles in subjects with Tourette Syndrome from two genetically isolated populations

BACKGROUND

Tourette Syndrome (TS) has a complex etiology and wide variability in phenotypic expression. Identifying underlying symptom patterns may be useful for etiological and outcome studies of TS.

METHODS

Lifetime tic and related symptom data were collected between 1996 and 2001 in 121 TS subjects from the Central Valley of Costa Rica and 133 TS subjects from the Ashkenazi Jewish (AS) population in the US. Subjects were grouped by tic symptoms using an agglomerative hierarchical cluster analysis. Cluster membership was tested for association with available ancillary information (age of onset, tic severity, comorbid disorders, medication treatment and family history).

RESULTS

Cluster analysis identified two distinct groups in each sample, those with predominantly simple tics (cluster 1), and those with multiple complex tics (cluster 2). Membership in cluster 2 was correlated with increased tic severity, global impairment, medication treatment, and presence of comorbid obsessive-compulsive symptoms in both samples, and with family history of tics, lower verbal IQ, earlier age of onset, and comorbid obsessive-compulsive disorder and attention-deficit/hyperactivity disorder in the AS sample.

CONCLUSIONS

This study provides evidence for consistent and reproducible symptom profiles in two independent TS study samples. These findings have implications for etiological studies of TS.

Relationship of movements and behaviors to Group A Streptococcus infections in elementary school children

BACKGROUND

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus (PANDAS) research is based on the hypothesis that infections trigger changes in behavior and movement in children.

METHODS

We enrolled 693 children (ages 3 to 12 years) into a systematic, longitudinal study. Data were collected monthly for 8 months (October-May) to determine point prevalence of Group A Streptococcal (GAS) infections, tics, behavior, and choreiform movements. Simultaneous throat cultures were obtained, and relational analyses were made between GAS and movement/observation ratings.

RESULTS

Combined behavior/GAS associations (concurrent with or 3 subsequent months to GAS) revealed a strong relationship, relative risk (RR) of 1.71 (p < .0001). Detailed analysis revealed that balance/swaying and non-tic grimacing were responsible for a significant proportion of this association (RR = 2.92, p < .0001). A strong seasonal pattern was found, with fall being more significant for GAS infections and observation ratings (p < .0001) compared with winter/spring. Children with repeated streptococcus (n = 64) showed higher rates of behavior and distal choreiform observations (p = .005).

CONCLUSIONS

Motor/behavior changes were noted to occur in relationship to positive GAS culture with support that repeated GAS increases risk.

Psychopathological profile in children with chronic tic disorder and co-existing ADHD: additive effects

The nature of the co-occurrence of chronic tic disorders (CTD) and attention deficit hyperactivity disorder (ADHD) is unclear. Especially in the field of psychopathology, the relationship of CTD and ADHD remains to be clarified. Thus, the aim of the present chart review study was to specify the contribution of CTD and/or ADHD to the psychopathological profile of the comorbid group (CTD+ADHD). The psychopathological profiles of four large groups (CTD-only (n=112), CTD+ADHD (n=82), ADHD-only (n=129), controls (n=144)) were measured by the eight subscales of the Child Behavior Checklist (CBCL) and analyzed by a 2x2 factorial design followed by contrasts. There were main effects of ADHD diagnosis on all but one subscale of the CBCL (Somatic Complaints). For CTD diagnosis, main effects were found for Attention Problems, Anxious/Depressed, Thought Problems, Social Problems and Somatic Complaints. The only interaction effect was seen for Somatic Complaints. While CTD and ADHD were both related to internalizing psychopathology of children in the CTD+ADHD group, ADHD had the largest effect on externalizing psychopathology in the comorbid group. At the level of psychopathology, an additive model for the co-occurrence of CTD and ADHD is strongly supported. In the comorbid group (CTD+ADHD), the ADHD diagnosis shows the strongest relation to externalizing psychopathology.

Psychopathology in a Swedish population of school children with tic disorders

OBJECTIVE

To examine patterns of psychiatric comorbid disorders and associated problems in a school population of children with tic disorders.

METHOD

From a total population of 4,479 children, 25 with Tourette's disorder (TD), 34 with chronic motor tics (CMT), 24 with chronic vocal tics (CVT), and 214 with transient tics (TT) during the past year were found. A three-stage procedure was used: tic screening, telephone interview, and clinical assessment. The TD group was compared with 25 children with TT and 25 controls without tics.

RESULTS

Psychiatric comorbid disorders were found in 92% of the children with TD. Attention-deficit/hyperactivity disorder was most common, and patterns of psychiatric comorbidity were similar in children with TD and CVT, but not with CMT and TT. Aggressive behavior was more common in children with TD than other tic disorders.

CONCLUSIONS

Psychiatric comorbid disorders are common even in community-based samples of children with TD and CVT. TD and CVT seem to be part of the same disease entity, with TD being a more severe form. Chronic tics may be a marker for behavioral and learning difficulties in children, and awareness of these associations is critical to the care and treatment of children with tics.

Executive functioning in children with autism and Tourette syndrome

The main aims of this study were to investigate if children with high-functioning autism (HFA) and children with Tourette syndrome (TS) can be differentiated in their executive functioning (EF) profile compared to normal controls (NCs) and compared to each other and to investigate whether children with HFA or children with TS and a comorbid group of children with both disorders are distinct conditions in terms of EF, Four groups of children participated in this study: HFA, TS, comorbid HFA + TS, and a NC group. All children were in the age range of 6 to 13 years. The groups were compared on five major domains of EF: inhibition, visual working memory, planning, cognitive flexibility, and verbal fluency. Children with HFA scored lower than NC children on all the EFs measured. Children with TS and NC children showed the same EF profile. The HFA group scored lower than the TS group for inhibition of a prepotent response and cognitive flexibility. Children with HFA performed poorer than children with comorbid HFA + TS on all functions, with the exception of inhibiting an ongoing response, interference control, and verbal fluency. Children with TS and children with comorbid HFA + TS could not be differentiated from one another in terms of EF. This study indicates that EF deficits are highly characteristic of children with HFA in comparison to children with TS and NC. The results suggest that for the comparison between HFA and TS groups, it is important to take into account comorbidity. A reevaluation of the EF hypothesis in children with TS is suggested.

Identification of pyruvate kinase as an antigen associated with Tourette syndrome

Immune responses to beta-hemolytic streptococcal infections are hypothesized to trigger tic disorders and early-onset obsessive-compulsive disorder (OCD) in some pediatric populations. Here we identify the M1 isoform of the glycolytic enzyme, pyruvate kinase (PK) as an autoimmune target in Tourette syndrome and associated disorders. Antibodies to PK reacted strongly with surface antigens of infectious strains of streptococcus, and antibodies to streptococcal M proteins reacted with PK. Moreover, immunoreactivity to PK in patients with exacerbated symptoms who had recently acquired a streptococcal infection was 7-fold higher compared to patients with exacerbated symptoms and no evidence of a streptococcal infection. These data suggest that PK can function as an autoimmune target and that this immunoreactivity may be associated with Tourette syndrome, OCD, and associated disorders.

Increased antistreptococcal antibody titers and anti-basal ganglia antibodies in patients with Tourette syndrome: controlled cross-sectional study

The association between Tourette syndrome, attention-deficit hyperactivity disorder (ADHD), and obsessive-compulsive disorder following streptococcal infections has been documented, but with conflicting reports. We thus felt it was important to investigate this association in a group of Italian patients not previously documented. We took blood on 69 patients with Tourette syndrome and 72 age- and sex-matched tic-free controls. Laboratory staff were blind to the diagnostic status of the subjects. Evidence of recent streptococcal infection was defined using antistreptolysin titers. Anti-basal ganglia antibodies were determined using human basal ganglia sections. Statistical analysis was conducted using analysis of variance and chi-square tests. Raised antistreptolysin titers were found in 41 of 69 (59%) patients with Tourette syndrome and 14 of 72 (19%) controls (P = .000). Positive anti-basal ganglia antibodies were found in 22 of 69 (32%) subjects with Tourette syndrome compared with 7 of 72 (10%) controls, which was also significant (P = .002). Raised antistreptolysin titers were detected in 18 of 22 (82%) patients with Tourette syndrome with positive anti-basal ganglia antibodies and 22 of 47 (47%) patients with negative anti-basal ganglia antibodies (P = .01). These results support the reported association between streptococcal infection and anti-basal ganglia antibodies and some patients with Tourette syndrome.

Co-occurring psychiatric disorders in children and adolescents with Tourette syndrome

More than half of all children and adolescents with Tourette syndrome show evidence of psychiatric comorbidity, exhibiting symptoms of attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, and other anxiety and mood disorders. Although the prevalence of co-occurring conditions varies depending on the clinical setting, it is crucial for clinicians to be familiar with these disorders because they are often more impairing than tics and can influence the initial treatment choice. Left untreated, these conditions can negatively affect important developmental outcomes, such as academic and social functioning. We review the most common co-occurring disorders, the relationship of these co-occurring disorders to Tourette syndrome, and treatment recommendations for co-occurring conditions when tic symptoms are present.

Tic disorders and obsessive compulsive disorder: where is the link?

Over the last years evidence on the overlap between tic-disorders (TD) and obsessive compulsive behavior/disorder (OCB/OCD) has increased. The main focus of research have been the phenomenological and epidemiological similarities and differences in samples of different age, primary diagnosis (TD vs. OCD) including the co-occurrence of both. Unfortunately, only a minority of studies included all three groups (TD, TD + OCD, OCD). Nevertheless, new insight concerning possible subtypes for both TD and OCD has been gained. While some authors concentrated on OCD with/without tics we will summarize the field of TD and OCB/OCD from the viewpoint of tics, since OCB plays an important role in patients with TD. Thereby we will not only sharpen the clinicans' awareness of known differences in phenomenology, epidemiology, genetics and neurobiology, aimed to improve their diagnoses and treatment but also highlight the gaps of knowledge and discuss possibilities for further research in this field.

Recent advances in Tourette syndrome research

Tourette syndrome (TS) is a developmentally regulated neurobehavioral disorder characterized by involuntary, stereotyped, repetitive movements. Recent anatomical and neuroimaging studies have provided evidence for abnormal basal ganglia and dopaminergic function in TS. Basic research on striatal inhibitory mechanisms and dopaminergic function complements the recent neuroimaging and anatomical data. Parallel studies of basal ganglia participation in the normal performance and learning of stereotyped repetitive behaviors or habits has provided additional insight. These lines of research have provided new pieces to the TS puzzle, and their increasing convergence is showing how those pieces can be put together.

Attention deficit hyperactivity disorder, tics and Tourette's syndrome: the relationship and treatment implications. A commentary

Tourette's Syndrome (TS) is now recognised to be a common childhood onset neurodevelopmental disorder. Attention deficit hyperactivity disorder (ADHD) is also a common childhood disorder. There are many cases in which the two disorders are comorbid. The reasons for this are unclear, but the comorbidity does not necessarily point to one genetic cause. Sleep is also often disturbed in individuals with TS and ADHD. The treatment implications of ADHD in the setting of tics or TS are important. Clonidine is suggested as a first line treatment. It was once thought that stimulants were contraindicated in the treatment of ADHD in the setting of TS, whereas it is suggested that they may be safe, but should be used judiciously. In addition, it was once thought that the combination of stimulants and clonidine was contraindicated, but from a large study the combination does appear to be safe. A relatively new medication for ADHD is atomoxetine, and although not documented widely in the setting of tics and TS, it may prove useful in this setting; further research is required. This commentary briefly discusses the comorbidity between TS and ADHD and offers treatment suggestions.

Comparison of DSM-IV symptoms in elementary school-age children with PDD versus clinic and community samples

This study compares DSM-IV symptoms in children (ages 6 to 12 years) with pervasive developmental disorder (PDD), clinic controls, and community-based samples. Parents/teachers completed the Child Symptom Inventory-4 for four samples: PDD (N = 284/284) and non-PDD psychiatric clinic referrals (N = 189/181) and pupils in regular (N = 385/404) and special (N = 61/60) education classes. The PDD group received higher symptom severity ratings than the regular education group, but was similar to the non-PDD clinic sample. Screening prevalence rates were highest for ADHD, ODD, and generalized anxiety disorder. PDD subtypes exhibited differentially higher rates of psychiatric symptoms. The magnitude of rater and gender differences in symptom severity ratings was modest. Clinic-referred children with PDD exhibit a pattern of psychiatric symptoms highly similar to nonPDD clinic referrals. Although much additional research is needed on comorbidity, these symptoms have important treatment implications.

Gilles de la Tourette syndrome: response to electroconvulsive therapy

Tourette syndrome is a chronic disease characterized by vocal and motor ticks. Self-injurious behavior is observed in one third of the patients and can be life-threatening. Current medical therapy includes dopamine receptor antagonists and atypical antipsychotics. In certain cases, there has been some evidence about the efficacy of electroconvulsive therapy (ECT). The case study below is a Tourette syndrome patient with self-injurious behavior and psychotic features and poor response to medical therapy. Two years of remission was achieved after 7 sessions of ECT and carbamezapine maintance therapy. In conclusion, ECT can be used as an efficacious treatment modality for Tourette patients with self-injurious behavior, psychotic features, or for those that are unresponsive to traditional methods.

Childhood onset neuropsychiatric disorders in adult eating disorder patients. A pilot study

BACKGROUND

Autism spectrum disorders (ASD) have been suggested to be overrepresented in anorexia nervosa. This study aimed to explore the comorbidity of ASD and other childhood onset neuropsychiatric disorders (COND) [attention-deficit/hyperactivity disorder (AD/HD) and tic disorders] in a group of severe eating disorder (ED) patients.

METHOD

Thirty female ED patients from a specialist hospital clinic were examined on measures tapping into COND and personality disorders.

RESULTS

In our group of longstanding ED, 53% had at least one COND diagnosis; 23% had ASD, 17% had AD/HD, and 27% had a tic disorder.

CONCLUSIONS

These preliminary data suggest that COND may be common in patients with severe ED and should be kept in mind when treating these patients.

Gilles de la Tourette's syndrome and its impact in the UK

Gilles de la Tourette's syndrome of chronic multiple motor and vocal tics is now acknowledged to be far more common than once thought, affecting up to 1% of schoolchildren with a wide range of severity. At the milder end of the spectrum the associated psychopathologies can in themselves impair social and educational functioning, in particular obsessive compulsive disorder and attention deficit hyperactivity disorder. Many patients with this condition are not being adequately served by health and education services in the UK. The epidemiology, clinical features, aetiological factors, and management of the syndrome are reviewed.

Behavioural problems and psychiatric symptoms in 5-13 year-old Swedish children-a comparison of parent ratings on the FTF (Five to Fifteen) with the ratings on CBCL (Child Behavior Checklist)

As part of the validation procedure of a new parent questionnaire ("Five to Fifteen" or the FTF) a random sample of 1500 children aged 5-13 years from the Swedish Population Register (SPAR) was approached. The FTF and the Child Behavior Checklist (CBCL) were sent to the parents of the children together with questions about background conditions. After two reminders the response rate was 55.6%. The final sample had a mean age of 9.12 years (SD=1.89) and a sex distribution with 55% boys and 45% girls. Analysis of attrition did not support overrepresentation of foreigners/immigrants in the attrition population. FTF like CBCL showed sensitivity to sociodemographic variables. On the FTF fewer problems were indicated for girls in all domain scales, whereas this was true for the summary scale Externalizing and Mixed problems of the CBCL. The effects of age and area of residence were slight, but parental education was negatively related to all domain scales of the FTF and to all the CBCL scales. The intercorrelations of the FTF and CBCL scales with common content showed substantial overlap supporting the validity of the FTF scales. The correlation between scales within the FTF however also indicates a substantial comorbidity. This is also supported by the substantial correlation between problem score of the FTF domains perception, language, motor skills and the CBCL scale scores Attention, Social problems as well as the summary scale Mixed problems. These findings indicate that problems with inattention and social relations are shared across the various problem domains. Factor analysis of the FTF subdomain scores resulted in two factors, one representing learning problems and the other behavioural/emotional problems. Despite the low response rate the representativity of the sample was supported by the fact that the total problem score of CBCL was very similar to that of another Swedish sample with a relatively high response rate. The finding of a frequency of AD/HD symptoms in the FTF rating corresponding to the figures of prevalence of AD/HD in several international epidemiological studies could also be seen as support for the relevance of the findings. Thus, the results give support to the usefulness of the FTF questionnaire as an instrument that can help in delineating specific problem areas within the field of child neuropsychiatry. Through the comparison with the CBCL the validity of the FTF for the parts that the two instruments share could be ascertained and the value of tapping a broader problem area could be elucidated.

Adult-onset tic disorder, motor stereotypies, and behavioural disturbance associated with antibasal ganglia antibodies

The onset of tics in adulthood is rare and, unlike the childhood variety, there is commonly a secondary environmental cause. We present four cases (1 man, 3 women) with an adult onset tic disorder (mean age of onset, 36 years; range, 27-42 years) associated with the presence of serum antibasal ganglia antibodies (ABGA). One patient had motor tics and unusual motor stereotypies, 2 had multiple motor and vocal tics, and the remaining patient had motor tics only. Concomitant psychiatric disturbance was noted in 3 cases. In 2 cases, there was a close temporal relationship between upper respiratory tract infection and the subsequent onset of tics. Imaging was possible in three cases and was normal in two but revealed a lesion involving the right caudate and lentiform nuclei in the other. We suggest that there might be a causal relationship between ABGA and the clinical syndrome in these cases and that ABGA should be considered as a possible etiology for adult-onset tics.

Clinical neuropsychiatric symptoms in perpetrators of severe crimes against persons

The objective of the study was to explore the possibility of common signs and symptoms of childhood-onset neuropsychiatric disorders and personality disorders, especially psychopathy, in a cohort of violent offenders. A structured neuropsychiatric status comprising features recorded in childhood-onset neuropsychiatric disorders and adult personality disorders was assessed in 89 perpetrators of severe crimes against other persons, analysed for factor structure, and compared to clinical diagnostics of neuropsychiatric disorders and independent assessments of psychopathy rated by the Psychopathy Checklist Revised (PCL-R). One or several childhood-onset neuropsychiatric disorders [autism, attention-deficit/hyperactivity disorder (AD/HD), tics and learning disability] affected the majority of adult offenders. A factor analysis yielded four higher-order problem constellations: Executive Dysfunction, Compulsivity, Social Interaction Problems and Superficiality. All four constellations were positively correlated with life histories of aggression, stressing the clinical importance of these problems in adult forensic psychiatry. Compulsivity and Social Interaction Problems were associated with autistic traits and tics, Executive Dysfunction with AD/HD, conduct disorder and psychopathic as well as autistic traits. Superficiality was a distinct aspect of AD/HD and psychopathic traits, especially the PCL-R factor reflecting interpersonal callousness. Neuropsychiatric disorders and personality disorders such as psychopathy share common symptoms. The various facets of psychopathy are associated with executive dysfunction and empathy deficits with superficial understanding of self, others and the rules of communication.

Psychiatric symptoms in preschool children with PDD and clinic and comparison samples

OBJECTIVE

This study describes and compares the severity of DSM-IV symptoms in preschool children with diagnosed pervasive developmental disorder (PDD), clinic controls, and two community-based samples.

METHOD

Parents (/and teachers) completed the early child inventory-4 (ECI-4), a DSM-IV-referenced rating scale for four samples: PDD (n = 172/160) and nonPDD psychiatric clinic referrals (n=135/101) and youngsters in regular (n=507/407) and special (n =64/140) early childhood programs. Children ranged in age from 3 to 5 years old.

RESULTS

With the exception of conduct problems, the PDD group generally received higher symptom severity ratings than the regular early childhood group, but the pattern of differences compared with the other two groups often varied by type of symptom and informant. Teachers rated the PDD and nonPDD clinic groups as having equally severe ADHD and oppositional defiant disorder symptoms. Teachers rated the PDD group as having more severe anxiety and depression symptoms than parents. The Asperger group was rated by both informants as more oppositional than the autism and PDDNOS subgroups. Teachers rated males in the regular early childhood sample as having more severe ADHD and aggressive symptoms than females, but this was not the case for the PDD sample.

CONCLUSION

Preschoolers with PDD exhibit more severe DSM-IV psychiatric symptoms than children in regular and special early childhood programs, and to some extent nonPDD psychiatric referrals. The concept of comorbidity warrants further exploration, as does informant-specific syndromes as validators of diagnostic constructs.

Olanzapine in the treatment of aggression and tics in children with Tourette's syndrome--a pilot study

OBJECTIVE

The aim of this study was to examine the effects of olanzapine on aggressive behaviour and tic severity in children with Tourette's Syndrome (TS).

METHOD

Ten (10) subjects (aged 7-13 years) with a primary diagnosis of TS and a history of aggressive behaviour were treated in a single-blind, 2-week placebo run-in, 8-week treatment phase trial. The starting dose of olanzapine was 1.25-2.5 mg/day and was titrated at biweekly intervals, as tolerated. The mean dosage at the end of the trial was 14.5 mg/day.

RESULTS

All 10 subjects completed the study. Olanzapine produced clinically and statistically significant reductions of aggression and tic severity from baseline to trial completion, as measured by the Achenbach Child Behavior Checklist (CBCL) and Yale Global Tic Severity Scale (YGTSS). Weight gain during the treatment period was the most common adverse effect (range 2-20 lbs: group mean 12.0 lbs +/- 5.71). No other significant adverse effects were observed during the 10-week trial.

CONCLUSION

The results of this trial confirm clinical observations that olanzapine may be an effective treatment for aggression and tics in children with Tourette's syndrome. Olanzapine was generally well tolerated, although significant weight gain was observed throughout the trial.

The common variants/multiple disease hypothesis of common complex genetic disorders

Unlike simple rare Mendelian disorders, the genetic basis for common disorders is unclear. A general model of the genetics of common complex disorders is proposed which emphasizes the shared nature of common alleles in related common disorders, such as schizophrenia and bipolar disorder, Type II diabetes and obesity, and among autoimmune diseases. This model, the common variants/multiple disease hypothesis, emphasizes that many disease genes may not be disease specific. Common deleterious alleles, found at a relatively high frequency in the population may play a role in related clinical phenotypes in the context of different genetic backgrounds and under different environmental conditions.

Lower limb motor restlessness in Asperger's disorder, measured using actometry

The movement disturbances and brain imaging findings in Asperger's disorder (AD) suggest a dopaminergic deficit in movement regulation. Movement disorders of different etiologies have been quantified and specified with actometry. We compared 10 AD patients with 10 healthy controls, measuring their rest-activities by actometry. The lower limb motor activity was significantly higher in the AD group. They also displayed a rhythmic, periodic movement pattern similar to akathisia. These findings suggest a hypothesis of idiopathic akathisia and a special sensitivity to adverse effects of neuroleptic drugs.

Relative contribution of attention-deficit hyperactivity disorder, obsessive-compulsive disorder, and tic severity to social and behavioral problems in tic disorders

The aim of this study was to investigate social and behavioral problems related to attention-deficit hyperactivity disorder (ADHD), obsessions and compulsions, and tic severity in children with a tic disorder. Parents of 58 children with a tic disorder with and without different forms of ADHD completed the Child Behavior Checklist (CBCL) and the Children's Social Behavior Questionnaire. Patients with a tic disorder with primarily hyperactive-impulsive ADHD had the highest questionnaire scores, patients with primarily inattentive ADHD had medium scores, and patients without ADHD had the lowest scores. On most subscales, significant part correlations with ADHD severity, but not tic severity, were obtained. Severity of obsessions and compulsions was independently correlated with the CBCL Thought Problems subscale but not with most other subscales. There was no significant correlation between tic severity and ADHD severity. Thus, in patients with a tic disorder, the presence and severity of ADHD are the main predictors of associated behavioral and social problems.

Prospective longitudinal study of children with tic disorders and/or obsessive-compulsive disorder: relationship of symptom exacerbations to newly acquired streptococcal infections

BACKGROUND

It has been proposed that infection by group A beta-hemolytic streptococci (GABHS) can trigger acute symptom exacerbations among patients with Tourette's syndrome (TS) or obsessive-compulsive disorder (OCD), via autoimmune mechanisms.

OBJECTIVE

To examine the temporal relationship between newly acquired GABHS infections (and other immunologic indices) and acute exacerbations of tics and obsessive-compulsive symptoms.

METHODS

Pediatric patients (7-17 years of age) with TS and/or OCD (N = 47) and healthy control subjects (N = 19) were prospectively monitored for newly acquired GABHS infections, nonspecific markers of acute inflammatory responses, and D8/17-reactive cells (a marker of rheumatic fever). Objective monthly ratings of tic and obsessive-compulsive symptom severity were used to determine the timing of symptom exacerbations.

RESULTS

The overall rate of acute exacerbations of neuropsychiatric symptoms was 0.56 exacerbations per patient per year. The average rate of new GABHS infections, using a stringent definition, was 0.42 infections per subject per year among patients, compared with 0.28 infections per subject per year for control subjects. The association between symptom exacerbations and new GABHS infections among patients was no greater than that expected on the basis of chance. At baseline, patients demonstrated significantly higher levels of D8/17-reactive cells and neopterin, compared with control subjects, but there was no consistent pattern of change when exacerbation time points were compared with baseline or follow-up time points.

CONCLUSIONS

The results suggest no clear relationship between new GABHS infections and symptom exacerbations in an unselected group of patients with TS and/or OCD.

Clinical features and associated psychopathology in a Tourette syndrome cohort

OBJECTIVE

This study explored in detail the association between tic symptomatology, related clinical variables, and psychopathology in 91 consecutive adult TS subjects from a UK clinic.

METHODS

Consecutive patients from a specialized Tourette clinic who met the DSM-III criteria for TS were evaluated using standardized rating scales for Tourette syndrome and other psychopathology.

RESULTS

The male female ratio in our cohort was 1.8:1. Significantly more males had an earlier age at onset of TS and history of birth complications. Obsessive compulsive behaviors in the patient was positively correlated with presence of attention deficit hyperactivity disorder and self-injurious behaviors. With regard to adult psychopathology, principal components factor analysis yielded two factors, 'obsessionality' and 'anxiety/depression', which accounted for 72% of the variance.

CONCLUSION

Our results support the high occurrence of anxiety, depression and obsessionality in adult TS subjects.

Movement Disorders

This chapter covers five movement disorders: Parkinson's disease, dystonia, tic disorders, Huntington's disease, and essential tremor. These disorders demonstrate many of the most common challenges encountered in the epidemiologic investigation of movement disorders. Each section includes a description of the disease, followed by a review of descriptive studies (disease incidence, prevalence, and mortality studies), and discussion of genetic and environmental risk factors for the disorder. At the end of each section, directions for future studies are discussed.

Adult psychopathic personality with childhood-onset hyperactivity and conduct disorder: a central problem constellation in forensic psychiatry

To describe lifetime mental disorders among perpetrators of severe inter-personal crimes and to identify the problem domains most closely associated with aggression and a history of repeated violent criminality, we used structured interviews, clinical assessments, analyses of intellectual functioning, medical and social files, and collateral interviews in 100 consecutive subjects of pretrial forensic psychiatric investigations. Childhood-onset neuropsychiatric disorders [attention-deficit/hyperactivity disorder (AD/HD), learning disability, tics and autism spectrum disorders] affected 55% of the subjects and formed complex comorbidity patterns with adult personality disorders [including psychopathic traits according to the Psychopathy Checklist (PCL-R)], mood disorders and substance abuse. The closest psychiatric covariates to high Lifetime History of Aggression (LHA) scores and violent recidivism were the PCL-R scores and childhood conduct disorder (CD). Behavioral and affective PCL-R factors were closely associated with childhood AD/HD, CD, and autistic traits. The results support the notion that childhood-onset social and behavioral problems form the most relevant psychiatric symptom cluster in relation to pervasive adult violent behavior, while late-onset mental disorders are more often associated with single acts of violent or sexual aggression.

Nicotinic acetylcholine receptors: from structure to brain function

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels and can be divided into two groups: muscle receptors, which are found at the skeletal neuromuscular junction where they mediate neuromuscular transmission, and neuronal receptors, which are found throughout the peripheral and central nervous system where they are involved in fast synaptic transmission. nAChRs are pentameric structures that are made up of combinations of individual subunits. Twelve neuronal nAChR subunits have been described, alpha2-alpha10 and beta2-beta4; these are differentially expressed throughout the nervous system and combine to form nAChRs with a wide range of physiological and pharmacological profiles. The nAChR has been proposed as a model of an allosteric protein in which effects arising from the binding of a ligand to a site on the protein can lead to changes in another part of the molecule. A great deal is known about the structure of the pentameric receptor. The extracellular domain contains binding sites for numerous ligands, which alter receptor behavior through allosteric mechanisms. Functional studies have revealed that nAChRs contribute to the control of resting membrane potential, modulation of synaptic transmission and mediation of fast excitatory transmission. To date, ten genes have been identified in the human genome coding for the nAChRs. nAChRs have been demonstrated to be involved in cognitive processes such as learning and memory and control of movement in normal subjects. Recent data from knockout animals has extended the understanding of nAChR function. Dysfunction of nAChR has been linked to a number of human diseases such as schizophrenia, Alzheimer's and Parkinson's diseases. nAChRs also play a significant role in nicotine addiction, which is a major public health concern. A genetically transmissible epilepsy, ADNFLE, has been associated with specific mutations in the gene coding for the alpha4 or beta2 subunits, which leads to altered receptor properties.

Phenomenology of tics and natural history of tic disorders

Tic symptoms, the hallmark of Tourette's syndrome (TS), may simply be fragments of innate behavior. As such, the sensory urges that precede tics may illuminate some of the normal internal cues that are intimately involved in the assembly of behavioral sequences. The occurrence of tics in time appears to have fractal characteristics that may help to explain the waxing and waning course of tic disorders. Longitudinal studies are currently underway that should permit a close examination of the natural fluctuations in tic severity using valid and reliable clinician-rated scales of tic severity. The natural history of tics typically shows a marked decline during the course of adolescence. However, TS can also be associated with social, emotional, and academic difficulties in early adulthood. Comorbid attention deficit/hyperactivity disorder and obsessive-compulsive disorder are likely to influence the long-term adaptive outcomes of individuals with TS. Future progress may also be expected as endophenotypes, and possibly genetic markers, are identified that are associated with specific comorbid conditions and etiologically distinct forms of TS.

Tourette's syndrome in Taiwan: an epidemiological study of tic disorders in an elementary school at Taipei County

We have done an epidemiological study in an elementary school with 2000 Taiwanese children aged from 6 to 12 years, and found 11 of them with Tourette's syndrome. The prevalence rate of Tourette's syndrome was around 0.56%. The ratio of male to female was 9 to 2. The comorbid rate of attention-deficit/hyperactivity disorder was 36%, self-injurious behaviors 27%, and obsessive-compulsive behaviors 18%. The familial rate of Tourette's syndrome was 27%. We also found that another 98 children had transient tic disorders. For 73% of patients with mild tics, understanding and acceptance from family, teachers, and friends are the most important things. When tics are so severe that medication is necessary, haloperidol is no longer the first or only choice. We tried clonidine, atypical neuroleptics such as risperidone or olanzapine, or pergolide. The first support group was established in 1999 for children with tics in Taiwan and transformed to Taiwan Tourette Family association in June 2001 to provide further service for Tourette's syndrome.

Psychological morbidity and caregiver burden in parents of children with Tourette's disorder and psychiatric comorbidity

OBJECTIVE

To investigate the mental health and caregiver burden in parents of children with Tourette's disorder (TD) compared with parents of children with asthma.

METHOD

A cross-sectional cohort survey was conducted at TD and pediatric asthma hospital outpatient clinics over a 6-month period. Main outcome measures were parent mental health (General Health Questionnaire [GHQ]-28) and caregiver burden (Child and Adolescent Impact Assessment) scores.

RESULTS

The response rate achieved was 89.7%. Of the parents of children with TD, 76.9% achieved caseness on the GHQ-28 compared with 34.6% of the parents of children with asthma; this effect remained significant after controlling for demographic variables. Parents of children with TD also experienced greater caregiver burden, and this burden was significantly correlated with GHQ caseness.

CONCLUSIONS

Parents of children with TD are at risk of psychiatric morbidity; an intervention targeting caregiver burden might be helpful in reducing this.

Diagnosing Tourette syndrome: is it a common disorder?

OBJECTIVES

The evaluate the prevalence of Tourette syndrome (TS).

METHODS

A review of the literature on TS was undertaken to examine the prevalence of TS in mainstream children as well as those in special education.

RESULTS

Recent studies have indicated that TS occurs in around 1% of youngsters in mainstream schools between the ages of 5 and 16 years. It is even more common in youngsters with special educational needs.

CONCLUSIONS

TS is more common than was previously documented.

Tourette's syndrome: a cross sectional study to examine the PANDAS hypothesis

BACKGROUND

The classical neurological disorder after group A beta haemolytic streptococcal infection is Sydenham's chorea. Recently a tic disorder occurring after group A streptococcal infection has been described and termed PANDAS (paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection). It is proposed that antibodies induced after group A streptococcal infection react with basal ganglia neurones in Sydenham's chorea and PANDAS. Anti-basal ganglia antibodies (ABGA) are present in most cases of acute Sydenham's chorea, but rarely in controls.

OBJECTIVE

To investigate the hypothesis that Tourette's syndrome may be associated with group A streptococcal infection and ABGA.

METHODS

100 patients with Tourette's syndrome (DSM-IV-TR) were enrolled in a cross sectional study. Children with neurological disease (n = 50) and recent uncomplicated streptococcal infection (n = 40), adults with neurological disease (n = 50), and healthy adults (n = 50) were studied as controls. Recent group A streptococcal infection was defined using antistreptolysin O titre (ASOT). ABGA were detected using western immunoblotting and indirect immunofluorescence.

RESULTS

ASOT was raised in 64% of children with Tourette's syndrome compared with 15% of paediatric neurological disease controls (p < 0.0001), and in 68% of adults with Tourette's syndrome compared with 12% of adult neurological controls and 8% of adult healthy controls (p < 0.05). Western immunoblotting showed positive binding in 20% of children and 27% of adults with Tourette's syndrome, compared with 2-4% of control groups (p < 0.05). The most common basal ganglia binding was to a 60 kDa antigen, similar to the proposed antigen in Sydenham's chorea. Indirect immunofluorescence revealed autoantibody binding to basal ganglia neurones. Serological evidence of recent group A streptococcal infection, assessed by a raised ASOT, was detected in 91% (21/23) of Tourette's syndrome patients with positive ABGA compared with 57% (44/77) with negative ABGA (p < 0.01).

CONCLUSIONS

The results support a role of group A streptococcal infection and basal ganglia autoimmunity in a subgroup of patients with Tourette's syndrome and suggest a pathogenic similarity between Sydenham's chorea and some patients with Tourette's syndrome.

A controlled study of psychopathology and associated symptoms in Tourette syndrome

BACKGROUND

Gilles de la Tourette syndrome (GTS) is a neurobehavioural disorder of genetic origin, although the precise inheritance pattern is as yet undetermined. This study was designed to describe symptomatology in GTS subjects. It describes the severity of depressive, anxiety and obsessional symptoms when compared to other samples of GTS patients, matched controls and normative data.

METHODS

87 consecutive GTS clinic referrals (children and adults) were interviewed in 1996 and 1997 using the National Hospital Interview Schedule, the Yale Global Tourette Severity Score, the Diagnostic Confidence Index, Beck Depression Inventory (BDI), Spielberger State-Trait anxiety Index (STAI) and Leyton Obsessional Inventory (LOI). 52 healthy controls were interviewed using the BDI, STAI and LOI. The clinical status of the subjects was described and ratings of psychopathology were compared with the control group and with normative data. Data were compared with previous data from similar clinic samples.

RESULTS

In this controlled study, GTS subjects scored highly on ratings of depression, state anxiety and obsessionality when compared with controls and with normative data. Scores in the subjects group were similar to previous findings in clinic samples of people with GTS.

CONCLUSIONS

People with GTS who attend clinics have a variety of psychological symptoms that are significantly more severe than controls. Accessory symptoms (e.g. coprophenomena, echophenomena) were also very common in the subject group. Psychological symptoms may occur as part of the disease, a reaction to disability or as a result of ascertainment bias.

Psychiatric disorders in individuals with pervasive developmental disorder

Pervasive developmental disorders (PDD) refer to the group of heterogeneous conditions that make up a continuum or spectrum of autistic disorders and share a core triad of impairments consisting of qualitative disturbances in social interaction and verbal and nonverbal communication and imagination. It has long been believed that the prevalence of autism was 2-4 per 10,000 children. However, studies using broader definitions of autistic disorder have suggested that the prevalence of autism spectrum disorder may be as high as 90 per 10,000 and that a greater proportion of individuals with PDD have intellectual levels above 70. Clinicians and researchers have commented on the apparent increase in prevalence of the disorder and have offered a number of explanations, including better recognition and diagnosis of the autism spectrum of disorders and a real increase in the disturbance. It is being increasingly recognized that individuals with PDD are at risk for a wide array of psychiatric disturbances, including affective disorder, anxiety disorders, schizophrenia-like psychosis, aggression, antisocial behavior, and Tourette's disorder (TD). Evidence indicates that PDD is significantly related to the comorbid psychiatric disorders and TD. Because PDD is not rare, individuals with autism spectrum disorder may represent significant subgroups of severely emotionally disturbed patients referred for psychiatric treatment. Because of lack of awareness that the clinical manifestations of PDD are heterogeneous and often mild and that comorbid psychiatric disturbances may obscure the symptoms of the developmental disorder, the diagnosis of PDD may be missed. Implications for practicing clinicians are discussed.

Disruptive behavior in children with Tourette's syndrome: association with ADHD comorbidity, tic severity, and functional impairment

OBJECTIVE

To examine the association of disruptive behavior with social, adaptive, and family functioning in Tourette's syndrome (TS) with and without comorbid attention-deficit/hyperactivity disorder (ADHD).

METHOD

The sample included 207 children (144 boys and 63 girls) between the ages of 7 and 18 years. Forty-two children received a diagnosis of TS-only, 52 received a diagnosis of ADHD-only, 52 children had TS+ADHD, and there were 61 unaffected control children. Best-estimate DSM-IV diagnoses were assigned on the basis of structured interviews and clinical ratings. Dependent measures included parent and teacher ratings of disruptive behavior, parent ratings of social and family functioning, and the Vineland Adaptive Behavior Scales.

RESULTS

Children with TS-only did not differ from unaffected controls on the parent ratings of aggression and delinquent behavior or on the teacher ratings of conduct problems. By contrast, children with TS+ADHD were rated significantly above unaffected controls and similar to children with ADHD-only on these indices of disruptive behavior. Hierarchical regression analyses revealed that aggression and delinquency scores added unique contributions to impairment in social and family functioning, controlling for age, gender, and diagnostic status.

CONCLUSIONS

Comorbid ADHD is highly associated with disruptive behavior and functional impairment in children with TS. When disruptive behavior problems are present, there is an additional burden on children's social and family functioning.

The epidemiology of autistic spectrum disorders: is the prevalence rising?

For decades after Kanner's original paper on the subject was published in 1943, autism was generally considered to be a rare condition with a prevalence of around 2-4 per 10,000 children. Then, studies carried out in the late 1990s and the present century reported annual rises in incidence of autism in pre-school children, based on age of diagnosis, and increases in the age-specific prevalence rates in children. Prevalence rates of up to 60 per 10,000 for autism and even more for the whole autistic spectrum were reported. Reasons for these increases are discussed. They include changes in diagnostic criteria, development of the concept of the wide autistic spectrum, different methods used in studies, growing awareness and knowledge among parents and professional workers and the development of specialist services, as well as the possibility of a true increase in numbers. Various environmental causes for a genuine rise in incidence have been suggested, including the triple vaccine for measles, mumps and rubella (MMR]. Not one of the possible environmental causes, including MMR, has been confirmed by independent scientific investigation, whereas there is strong evidence that complex genetic factors play a major role in etiology. The evidence suggests that the majority, if not all, of the reported rise in incidence and prevalence is due to changes in diagnostic criteria and increasing awareness and recognition of autistic spectrum disorders. Whether there is also a genuine rise in incidence remains an open question.

Delayed and severe but transient Tourette syndrome after head injury

A previously well and intellectually normal 7(1/2)-year-old girl developed an acute and severe Tourette syndrome 15 months after sustaining a severe head injury. The patient displayed a dramatic response to haloperidol. Twelve months after the onset of Tourette syndrome the haloperidol was withdrawn, and there was no relapse of either her motor or phonic tics. Seven years after the head injury the patient remains tic free but demonstrates significant emotional and behavioral sequelae. The patient's brain magnetic resonance imaging findings were consistent with those reported previously in adults with Tourette syndrome.

Tics and its disorders

Tourette syndrome (TS) is familial neuropsychiatric disorder that is characterized by motor and phonic tics that begin in childhood. Once thought of as a rare and debilitating disorder, in the last decade new scientific knowledge suggests that TS and related tic disorders are more common and less debilitating for the majority of individuals. Evidence points toward a spectrum of TS symptomatology that extends beyond the tics disorder to probably include obsessive-compulsive disorder, attention deficit hyperactivity disorder, and mood disorders. Tourette syndrome and its differential diagnosis are discussed in this article with a focus on new developments in classification, etiology, epidemiology, genetics, pathophysiology, and clinical management.

Obsessive-compulsive disorder and tic syndromes

The phenomenology of OCD and TS seem to match perfectly with the existing conceptualization of the functional relationship between frontal cortical and subcortical circuits. Failed editing of thoughts and impulses, perseverative patterns, and inhibitory deficits are the most convenient descriptors of the symptoms, and some operationalized measures can capture evidence for such deficits in TS and OCD patients. Beyond these expectations borne from conceptual models and some broad patterns of distributed metabolic disturbances in neuroimaging studies, a specific causal pathology within CSPT circuitry needs to be identified in these disorders. This is not a criticism of the existing studies of TS and OCD; to the contrary, the scarcity of pathologic material, the limits of resolution of existing technologies, and the heterogeneity of the phenotypes make the accomplishments of these studies more impressive. As clinicians strive to integrate clinical and scientific findings into coherent models for the pathophysiology of OCD and TS, it is useful to identify practical and effective strategies for therapeutic interventions.