Non-Obscene Socially Inappropriate Behavior in Patients with Gilles de la Tourette Syndrome

Background/Objectives: Behavioral disturbances are a common phenomenon associated with Gilles de la Tourette syndrome (GTS), which can manifest as non-obscene socially inappropriate behaviors (NOSIBs). The classification of NOSIB has not yet been clearly established. The objective of this study was to determine the frequency, age of onset, and clinical correlation of NOSIB with tic severity and the prevalence of comorbid psychiatric disorders in individuals with GTS. Methods: A total of 365 participants (272 male, 74.5%) with GTS were included in the study. Of these, 278 (76.2%) were children and adolescents. The mean age of the participants at evaluation was 14.4 ± 9.8 years, with a range of 4 to 64 years. The clinical data of NOSIB were collected during a routine, ambulatory examination using half-structured questionnaires developed by the authors. Results: NOSIB was observed in 86 patients with GTS, representing a prevalence of 23.6%. NOSIB commenced at a mean age of 6.6 ± 4.1 years (range 2-19). The mean age at onset of NOSIB was 1.4 ± 3.7 years after the onset of tics, with 18 cases (26.1%) preceding tics and 13 cases (18.8%) starting at the same age as tics. The results of the multivariate analysis confirmed the associations between NOSIB and YGTSS (p = 0.02) and coprophenomena (p < 0.01), as well as ADHD (p < 0.01), ODD (p = 0.01), ASD (p < 0.01), and anxiety disorders (p = 0.02). Conclusions: NOSIB is an early symptom of GTS that typically manifests in childhood and occurs in approximately a quarter of patients. Tic severity and the presence of psychiatric comorbidities, which indicate a more severe disease course, may serve as risk factors for NOSIB.