Exercise and mental illness: results from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC).

BACKGROUND: Regular exercise is thought to be associated with low rates of mental illness, but this association has been inadequately studied. The purpose of this study was to test the hypotheses that the recommended amount of self-reported vigorous exercise would be cross-sectionally associated with reduced prevalence and incidence of various DSM-IV psychiatric disorders, as well as increased rates of remission.
METHOD: Data were collected from 2001 to 2005 as part of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a 2-wave face-to-face survey conducted by the National Institute on Alcohol Abuse and Alcoholism. For this study, the sample consisted of 23,505 nondisabled adults aged between 18 and 65 years.
RESULTS: Individuals who engaged in vigorous exercise at Wave 2 were significantly more likely than were nonexercisers to be diagnosed with a current psychiatric disorder (adjusted odds ratio [AOR] = 1.22, 95% CI, 1.12-1.34 for the nationally recommended amount vs no exercise), significantly less likely to attain remission from a psychiatric disorder between waves (AOR = 0.77, 95% CI, 0.65-0.91), and significantly more likely to relapse or be newly diagnosed with a psychiatric disorder between waves (AOR = 1.15, 95% CI, 1.02-1.30). Alcohol dependence and bipolar II disorder were the disorders most strongly associated with exercise.
CONCLUSIONS: This investigation suggests that the pursuit of vigorous exercise is associated with a vulnerability to mental illness. This surprising finding may be due to reward-related factors that influence both exercise engagement and the expression of certain psychiatric disorders. Prospective trials will be helpful in further clarifying the associations between exercise and mental illness, as the relationships between the 2 are more complex than previously believed. © Copyright 2012 Physicians Postgraduate Press, Inc.