Demographic and Clinical Characteristics Associated With Co-Occurring Psychopathology Among Adults Being Evaluated for Attention-Deficit/Hyperactivity Disorder

Introduction Psychiatric conditions often co-occur with Attention-Deficit Hyperactivity Disorder (ADHD), but limited literature exists on factors contributing to such comorbidity. This study examined how patient demographic and clinical characteristics were associated with co-occurring psychopathology among a clinical sample of adults with ADHD. Method Data were cross-sectional data from a consecutive clinical case series of 848 patients diagnosed with ADHD (n = 363) or ADHD and a co-occurring psychiatric disorder (n = 485) following neuropsychological evaluation. Results Significant differences emerged between groups by education, estimated IQ, and student status but with small, non-clinically relevant effect sizes. Females had nearly double the rate of co-occurring psychiatric disorder than males. Females diagnosed with ADHD were also twice as likely to be diagnosed with a co-occurring psychiatric disorder compared to males with ADHD (OR = 2.07; 95% CI = 1.54, 2.77). Lower education also was modestly associated with co-occurring psychopathology (OR = 0.87; 95% CI = 0.80, 0.94). Conclusion Results showed a strong association between female sex and being diagnosed with both ADHD and comorbid psychiatric illness. Clinicians should be attuned to these appreciably higher rates of comorbid internalizing psychopathology among females with ADHD so to not overlook and fail to treat active psychopathology that can contribute to the clinical picture during psychiatric evaluation for ADHD.