Prevalence and correlates of adult attention-deficit hyperactivity disorder: meta-analysis

BACKGROUND: In spite of the growing literature about adult attention-deficit hyperactivity disorder (ADHD), relatively little is known about the prevalence and correlates of this disorder. AIMS: To estimate the prevalence of adult ADHD and to identify its demographic correlates using meta-regression analysis. METHOD: We used the MEDLINE, PsycLit and EMBASE databases as well as hand-searching to find relevant publications. RESULTS: The pooled prevalence of adult ADHD was 2.5% (95% CI 2.1-3.1). Gender and mean age, interacting with each other, were significantly related to prevalence of ADHD. Meta-regression analysis indicated that the proportion of participants with ADHD decreased with age when men and women were equally represented in the sample. CONCLUSIONS: Prevalence of ADHD in adults declines with age in the general population. We think, however, that the unclear validity of DSM-IV diagnostic criteria for this condition can lead to reduced prevalence rates by underestimation of the prevalence of adult ADHD.