Co-occurring mental health disorders in a Brazilian sample of adults with autism spectrum disorder: A focus on gender disparities

INTRODUCTION: Adults with Autism Spectrum Disorder (ASD) often present with core symptoms and co-occurring conditions that require multidisciplinary support. The objective of this study is to describe the sociodemographic and clinical profile of a sample of Brazilian adults with ASD, with a focus on the prevalence of co-occurring mental health disorders and the investigation of gender-related disparities. METHODS: A total of 117 adults with a previous diagnosis of ASD (60.7% female; mean age = 31.84, SD = 10.03; age range: 18-61 years) were recruited by convenience sampling. Participants completed a sociodemographic and clinical history questionnaire. We analyzed associations between co-occurring mental health disorders and biological sex. RESULTS: Most participants had completed at least high school (95.7%). Co-occurring neurodevelopmental disorders were present in 35.9% of the sample. ADHD was the most common (30.8%). Co-occurring mental health disorders were reported by 75.2% of participants, with anxiety disorders being the most frequent (71.8%). A statistically significant gender disparity was observed, showing that women had a significantly higher prevalence of at least one mental health disorder (85.9% vs. 58.7%), anxiety (83.1% vs. 54.3%), and depression (62% vs. 37%) compared to men. CONCLUSION: While not generalizable due to the convenience sampling method, these results contribute to a growing body of evidence on the high rates of co-occurring mental health disorders in adults with ASD, especially in women. This study supports the call for an expanded research agenda in Brazil to better understand the clinical reality and guide future support strategies for this population.