American Journal of Epidemiology Advance Access published online on January 31, 2007
American Journal of Epidemiology, doi:10.1093/aje/kwk070
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ORIGINAL CONTRIBUTION |
Physical Activity and Common Mental Disorder: Results from the Caerphilly Study
1 Academic Unit of Psychiatry, Department of Community-Based Medicine, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom
2 Department of Exercise and Health Sciences, Faculty of Social Sciences and Law, University of Bristol, Bristol, United Kingdom
3 Department of Epidemiology, Statistics and Public Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
4 Department of Social Medicine, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom
Correspondence to Dr. Nicola J. Wiles, Academic Unit of Psychiatry, Department of Community-Based Medicine, University of Bristol, Cotham House, Cotham Hill, Bristol BS6 6JL, United Kingdom (e-mail: nicola.wiles{at}bristol.ac.uk).
The authors examined associations between leisure-time and occupational physical activity and common mental disorder (CMD), defined as anxiety and depression, using data from a cohort of middle-aged men in Caerphilly, South Wales, United Kingdom, who were followed for 5 years (1989–1993) and 10 years (1993–1997). CMD was measured using the General Health Questionnaire. Total leisure-time activity and percentage of time spent in heavy-intensity activity were estimated from self-reports (Minnesota Leisure Time Physical Activity Questionnaire). Men were classified into four classes of occupational activity. Among 1,158 men with complete data, those who participated in any heavy-intensity leisure-time activity had reduced odds of CMD 5 years later (below median vs. none: adjusted odds ratio (ORadj) = 0.61, 95% confidence interval (CI): 0.40, 0.93); median or above vs. none: ORadj = 0.54, 95% CI: 0.35, 0.83). Analyses using multiple imputation to deal with missing data found weaker evidence for an association (ORadj = 0.79 (95% CI: 0.54, 1.15) and ORadj = 0.73 (95% CI: 0.49, 1.09), respectively). There was little evidence that men in the most physically demanding jobs had reduced odds of CMD after 5 years, and there was no association between physical activity and CMD 10 years later. Among these men, heavy-intensity leisure-time physical activity was associated with a small reduction in CMD over 5 years.
anxiety; depression; exercise; mental disorders; physical fitness
Abbreviations: CI, confidence interval; GHQ-30, 30-item General Health Questionnaire; MICE, multiple imputation by chained equation; OR, odds ratio