LONG TERM USAGE OF ARIPIPRAZOLE IN TOURETTE SYNDROME

Introduction Tourette syndrome (TS) is a common neuropsychiatric disorder affecting 1% of children worldwide. Diagnostic criteria include the presence of multiple motor tics and at least one phonic tic for a period of at least one year, and more than 80% of patients exhibit comorbid psychiatric disorders. The mainstay of pharmacological management of tics has been using neuroleptics. Aripiprazole is an atypical antipsychotic uniquely with partial agonist effects at the D2–receptor, and other adrenergic and serotonergic actions. It is increasingly used for tics following open label series and one controlled study. However as for most of the literature in GTS, follow–up tends to be relatively short with the risk of overestimating the overall benefit of drugs for a condition that naturally fluctuates, displays variable responses between patients and is difficult to objectively measure even using the widely employed YGTSS rating scale. Methods Clinic letters from all TS patients prescribed Aripiprazole at a tertiary clinic between 2004 and 2012 were retrospectively analysed. Demographic, clinical and medication data were collated. In order to describe this homogeneous group a threshold of 12 months continuous supervised prescription of the drug was selected as a proxy for successful long–term usage. Reasons for cessation were also recorded. Results A cohort of 75 patients who had complete follow–up on the drug comprised 36 adult patients and 39 children under the age of 18 at a dose range of 2.5–20mg. The mean duration of Aripiprazole usage was 20.74 months (range: 1–96 months) in the adult group, and 20.55 months (range: 3 days–60 months) in the paediatric group. Over 65% of patients had been maintained on Aripiprazole for more than 12 months. The most common reasons for cessation of Aripiprazole before 12 months included side effects (70%) and inefficacy (22%). The average baseline YGTSS Motor score was significantly lower in the group that remained on Aripiprazole at 12 months compared to the group that had ceased medication at 12 months (p=0.013). Adverse effects were reported by 63.9% of the adult group and 61.5% of the paediatric group. The most common problems were sedation, increased appetite/weight gain, and gastrointestinal disturbances. Extra–pyramidal adverse effects were observed in 5 of the adult group and 2 of the children. Discussion This study demonstrates the long–term usefulness of Aripiprazole in TS, although not without significant adverse