RATES FOR TIC DISORDERS AND OBSESSIVE-COMPULSIVE SYMPTOMATOLOGY IN FAMILIES OF CHILDREN AND ADOLESCENTS WITH GILLES-DE-LA-TOURETTE-SYNDROME

The aim of this study was to assess rates for tic disorders and obsess ive compulsive psychopathology in families of children and adolescents with Gilles de la Tourette syndrome (TS). Diagnoses were based on the DSM III-R criteria. Obsessive compulsive psychopathology, that did no t fulfill the criteria for obsessive compulsive disorder (OCD) was add itionally assessed and termed obsessive compulsive symptoms (OCS). The authors hypothesized that comorbid OCD or OCS in TS patients predicts a higher familial loading with obsessive compulsive symptomatology. T he study cohort included 87 patients with TS who were evaluated clinic ally and with the use of a structured psychiatric interview. All avail able parents (152/174; 87%), several sibs (49/93; 53%) and some second degree relatives (27/659; 4.1%) were also interviewed. For other firs t and second degree relatives the family history method was used. Fami lial rates for TS were clearly elevated. Rates for chronic tic disorde rs (CT) were considerably lower than in previous studies. Additionally , tic disorders not otherwise specified (TDNOS) were diagnosed in a su bstantial number of first degree (15/267; 5.6%) and second degree rela tives (36/659; 5.5%). OCD in parents (4/174; 2.3%) did not occur in an above baseline rate. However, both OCD (14/87; 16.1%) and OCS (15/87; 17.2%) were frequently associated with TS in index patients. Interest ingly, 10 of 16 fathers with OCS also had a tic disorder. Obsessive co mpulsive psychopatholopy clustered in families. It is concluded that g enetic studies in TS could profit from adhering to a conservative diag nostic approach to both tic disorders and OCD. The familial clustering of OCS/OCD in conjunction with the elevated paternal rate for the co- occurence of tic disorders and OCS might indicate heterogeneity of TS. (C) 1997 Elsevier Science Ltd.