The role of impulse control disorders in Tourette syndrome: An exploratory study

Introduction: Tourette syndrome (TS) is a neurodevelopmental condition characterised by the presence of multiple motor tics and one or more phonic tics, often associated with co-morbid behavioural problems. Impulse control disorders (ICDs) are a set of disorders where patients have significant difficulties in controlling their urges to perform rewarding behaviours. ICDs are expected to be common in patients with TS, as many problems reported in TS are related to difficulties in controlling impulsivity. Aims: This exploratory study aimed to determine the clinical characteristics of ICDs in adult patients with TS, and to investigate the relationship between the presence of ICDs and health-related quality of life (HR-QOL). Methods: Thirty-one patients with a diagnosis of TS were screened for ICDs using the Minnesota Impulsive Disorders Interview (MIDI). HR-QOL was assessed using a generic instrument, the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and a disease-specific scale, the Gilles de la Tourette Syndrome-Quality of Life Scale (GTS-QOL). Results: Twenty-three out of 31 participants (74.2%) had at least one ICD. The most common ICDs were intermittent explosive disorder (51.6%) and compulsive buying disorder (41.9%). The number of ICDs significantly correlated with reduced HR-QOL (p = 0.011) as measured by the GTS-QOL, but not by the SF-36. Conclusions: ICDs are common in patients with TS. HR-QOL measures specific to this patient population show that the presence of co-morbid ICDs results in poorer HR-QOL.