The prevalence of adult attention-deficit hyperactivity disorder: A global systematic review and meta-analysis

BACKGROUND: Adult attention-deficit hyperactivity disorder (ADHD) has recently attracted much attention, however, an up-to-date estimation on the prevalence of adult ADHD is lacking. In this study, we aimed to assess the global prevalence of adult ADHD in the general population through a systematic review and meta-analysis. METHODS: PubMed, Medline, Embase and PsycINFO were searched to identify relevant articles published from January 2000 onwards. Population-based studies that were conducted in the general adult population and quantified the prevalence of adult ADHD were included. RESULTS: The prevalence of persistent adult ADHD (with a childhood onset) and symptomatic adult ADHD (regardless of a childhood onset) both decreased with advancing age. By adjusting for the global demographic structure in 2020, the prevalence of persistent adult ADHD was 2.58% and that of symptomatic adult ADHD was 6.76%, translating to 139.84 million and 366.33 million affected adults in 2020 globally. CONCLUSIONS: This study provides an up-to-date estimation of the global prevalence of both persistent and symptomatic adult ADHD. A well-defined strategy for diagnosing adult ADHD and large-scale investigations on the epidemiology of adult ADHD are needed.