A functional magnetic resonance imaging study of a large clinical cohort of children with Tourette syndrome.

There is evidence that cortico-striato-thalamo-cortical pathways are involved in the pathophysiology of Tourette syndrome. During the performance of neuropsychological tests in subjects with Tourette syndrome there are suggestions for increased activity in the sensimotor cortex, supplementary motor areas, and frontal cortex. To replicate findings, the authors examined 22 medication-naive children with Tourette syndrome only, 17 medication-naive children with Tourette syndrome and comorbidity, and 39 healthy controls with functional magnetic resonance imaging (MRI). There were no differences in activation in brain regions between the children with Tourette syndrome (divided according to the presence of comorbidity) and healthy controls after correction for the confounders age, sex, and intelligence. Activation in the cingulated gyrus, temporal gyrus, and medial frontal gyrus was correlated significantly with obsessive-compulsive disorder score. The authors did not find significant correlations between activation patterns and age, sex, duration of disease, intelligence, severity of tics, and attention-deficit hyperactivity disorder (ADHD) score.

Performance on Wechsler intelligence scales in children with Tourette syndrome.

BACKGROUND: There is some evidence that Tourette syndrome is associated with cognitive disabilities. AIMS: To examine the cognitive performance of a clinical cohort of children with Tourette syndrome. METHODS: 266 children with Tourette syndrome have been examined with Wechsler Intelligence Scales. The presence of the co-morbidities attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD) was assessed using validated diagnostic instruments. Eighty healthy controls matched a part of the TS cohort. RESULTS: The children with Tourette syndrome had a mean verbal IQ (VIQ) of 92.9, performance IQ (PIQ) of 87.1, and full-scale IQ (FSIQ) of 88.8. We found statistically significant higher PIQ and FSIQ in the control group compared with a matched TS cohort and a trend towards a higher VIQ among the healthy controls. There was a statistically significant influence of age at onset of tics on PIQ. The children with co-morbid OCD scored higher on FSIQ compared with the other groups. The children with co-morbid ADHD and OCD showed problems in motor tasks and speed tasks and the children with co-morbid ADHD showed attention deficits. CONCLUSIONS: Children with Tourette syndrome have lower IQ scores than the general population (but less than one standard deviation below) and our control group. Early onset of tics and the presence of co-morbidities might cause specific deficits on cognitive performance.

Predictive factors for familiality in a Danish clinical cohort of children with Tourette syndrome.

Tourette syndrome (TS) is a chronic, neurobiological disease, characterized by the presence of motor and vocal tics and it is often accompanied by associated symptoms. The two best-known co-morbidities are Obsessive-Compulsive Disorder (OCD) and Attention Deficit Hyperactivity Disorder (ADHD). The fact that TS aggregates strongly in families suggests that family members share either genetic and/or environmental risk factors contributing to TS. Numerous studies have been performed to examine the familiality in TS, but clear-cut factors to predict hereditability in TS have not been found yet. We have examined a large Danish clinical cohort of children with TS (N=307). Validated diagnostic instruments were used to assess the presence of co-morbidities in the children with TS. A three-generation pedigree was drawn for all the probands and through reports from the family, a family history and the frequency of affected relatives was noted. The rates of tics, symptoms of OCD, and ADHD among relatives are similar to the rates found in other countries and are higher than in the general population. Although the role of sex in determining the phenotype has to be examined more thoroughly, we found that male relatives were more likely to have tics and female relatives were more likely to have symptoms of OCD. When comparing the relatives to male patients with relatives to female patients, there were no differences in the rates of symptoms, apart from symptoms of ADHD that were more frequent in second-degree relatives to female patients. The severity of tics and the presence of co-morbidity did not seem to predict the familiality of TS and its associated symptoms.

The presence of comorbidity in Tourette syndrome increases the need for pharmacological treatment.

Tourette syndrome is often accompanied by other syndromes, like attention-deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder, and its treatment is symptomatic. Because there are no European guidelines for pharmacological treatment in Tourette syndrome, we wanted to contribute to a better insight into the common practice in Scandinavia. Furthermore, we wanted to elaborate the influence of the presence of comorbidities and of the severity of tics on pharmacological treatment. We have examined the frequency, art, and reason for pharmacological treatment in a Danish clinical cohort of 314 children with Tourette syndrome. In total, 60.5% of the children once had received pharmacological treatment. Mostly, the treatment was started because of tics or ADHD. If ADHD or obsessive-compulsive disorder were present, more children received pharmacological treatment and more different agents were tried. The children who received pharmacological treatment had more severe tics than those without medication.