[Tic disorders and arousal dysfunction: clinical evaluation of 49 children and adolescents]

Tourette Syndrome (TS) shows a significant comorbidity with obsessive-compulsive disorders, behavioral problems (i.e. attention-deficit/hyperactivity disorders) and sleep disturbances. Several studies showed that sleep problems are common in TS patients affecting 12% to 62% of patients. Aim of this study was to evaluate the relationships between tics, sleep disorders and behavioral disturbances.

Fourty-nine consecutive children and adolescents with tics have been studied by the following procedure: a) the Yale Global Tic Severity Scale (YGTSS) was administered in order to establish the severity of tics; b) the Child Behavior Checklist (CBCL) was used to evaluate behavioural disturbances; c) the Sleep Disturbance Scale for Children (SDSC) was filled out in order to assess the presence of sleep disorders. An age-matched control group was used for comparison.

All patients (either TS or non-TS) showed a higher prevalence of sleep disturbances versus the control group. Sleep-wake transition disorders (SWTD) were the most frequent sleep disturbances found in our sample, followed by disorders of initiating and maintaining sleep (DIMS). These latter sleep disturbances were highly correlated with the severity of tics. Internalization problems, anxiety/depression and attention and thinking problems were very frequent in our sample. Correlation analysis showed a positive relationship between internalization problems and DIMS and also between aggressive behaviour and respiratory disturbances during sleep (RDS).

The results obtained seem to confirm the literature reports on the strict relationship between tics and sleep disturbances, mainly SWTD, and further support the hypothesis of a dysfunction of arousal mechanism in TS.