Adult ADHD: Prevalence, Comorbidities, and Patient-Reported Dysfunction in a Tertiary Mental Health Clinic

Abstract

Background: To investigate patient-reported dysfunction associated with ADHD and three common comorbidities—major depressive disorder (MDD), generalized anxiety disorder (GAD), and bipolar disorder (BPD)—as well as their prevalence. Methods: Dysfunction was measured using the Sheehan Disability Scale (SDS). Diagnosis was attained by a certified psychiatrist using DSM-5 criteria. Results: In all, 46.7% of our sample (432/925) was diagnosed with ADHD. The most common comorbidities, in ascending order, were MDD (21.99%), BPD (24.77%), and GAD (31.48%). Sorted by ascending SDS score, the most functionally debilitating diagnoses in our sample were GAD < ADHD < ADHD + GAD < BPD < ADHD + BPD < MDD < ADHD + MDD. Conclusions: Our sample of adults with ADHD, GAD, BPD, and particularly MDD report significant daily dysfunction. Comorbid ADHD is associated with increased dysfunction, particularly with GAD. The prevalence of adult ADHD in our study was higher than in previous studies.