According to a study of more than 9,000 subjects in the National Comorbidity Survey Replication, 46% of U.S. adults have had a psychiatric disorder at some point in their lives. The study was conducted to update previous findings to include changes made in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and was reported in the June 6 issue of the Archives of General Psychiatry. Quite striking was the early age of onset of mental health disorders, often in childhood, adolescence, or young adulthood. Disorders that began later in life tended to be seen in people who already had at least one DSM-IV diagnosis. Anxiety and impulse control disorders, which began earliest in life (median age of onset, 11 years) were the most common groups of disorders, with estimated lifetime prevalence rates of 29% and 25%, respectively. The median age of onset of substance use disorders was 20, and the estimated lifetime prevalence was 15%. Mood disorders tended to appear later in life; the median age of onset (for any mood disorder) was 30; the lifetime prevalence was 21%. Major depression and alcohol abuse were the most common individual disorders, affecting 17% and 13% of the population. Estimated lifetime risk of any disorder was just over 46%. Psychiatric disorders were found to cause as much impairment as chronic physical disorders, and because they so often begin early in life, the societal burden they cause may be especially high. The study authors advocate "early interventions aimed at preventing the progression of primary disorders and the onset of comorbid disorders" in children and young adults. -Fran Mennick, BSN, RN

Kessler RC, et al. Arch Gen Psychiatry 2005;62(6):593-602.