Chronic Tic Disorders in Youth: Clinical Phenotypes and Response to Pharmacological Treatment with Aripiprazole.

Background/objectives: Tic disorders are neurodevelopmental conditions often associated with comorbidities like attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Our aims were: (a) in a sample of youth with tic disorders to explore the clinical and psychopathological characteristics of different phenotypes based on the presence of comorbid ADHD and/or ASD and gender; (b) in a subgroup of patients treated with Aripiprazole, to evaluate symptoms variation over time and to identify potential predictors of response.
Methods: A total of 95 subjects with tic disorders (age range 6 to 17.9 years, mean 11.1 ± 2.11 years, 80 males) were naturalistically recruited. Questionnaires and semi-structured interviews were administered to assess the symptomatology and investigate the presence of psychiatric comorbidities (Clinic Global Impression-Severity (CGI-S), Children's Global Assessment Scale (C-GAS), Yale Global Tic Severity Scale (YGTSS), Premonitory Urge for Tics Scale (PUTS), Child Yale-Brown Obsessive Compulsive Scale for Children (CYBOCS), Child Behavior Checklist 6-18 (CBCL 6-18), Conners' Parent Rating Scale-Revised-short form (CRSR-S), Reactivity Intensity Polarity Stability Questionnaire-youth version (RIPoSt-Y), and Social Communication Questionnaire-lifetime version (SCQ); Autism Diagnostic Observation Scale-second version (ADOS-2) and Autism Diagnostic Interview-revised version (ADI-R) were administered where ASD was suspected). A total of 22 subjects treated with Aripiprazole were reassessed through the use of some of the clinical measures used at baseline.
Results: The presence of ADHD was associated with higher externalizing problem scores on the CBCL 6-18, while ASD was linked to higher internalizing problem scores. A positive correlation was found between the ADHD-ASD interaction and increased internalizing symptoms on CBCL 6-18 and higher ADOS-2 scores. Patients treated with Aripiprazole showed significant improvement across all scales during follow-up. ADHD was identified as a negative predictor of reduced tic severity on the YGTSS.
Conclusions: Comorbid neurodevelopmental disorders, such as ADHD or ASD, result in worse emotional and behavioral functioning in patients with tic disorders. ADHD-ASD interaction may be linked to more internalizing symptoms and autistic behaviors. Aripiprazole improves overall clinical outcomes, although comorbid ADHD may hinder the reduction of tic symptoms.