Physical activity and risk of coronary heart disease in India.
BACKGROUND
Physical exercise has been inversely associated with coronary heart disease (CHD) risk in Western populations; however, the association has not been examined in India where physical inactivity levels in urban areas are now comparable with the West.


METHODS
We conducted a hospital-based case-control study and collected data from 350 cases of acute myocardial infarction and 700 controls matched on age, gender, and hospital in New Delhi and Bangalore. We used conditional logistic regression to control for the matching and other risk factors.


RESULTS
Of the controls, 48% participated in some form of leisure-time exercise compared with 38% of cases. In age- and sex-adjusted analyses, people in the highest level of leisure-time exercise (>145 metabolic equivalents [MET]-minutes per day, equivalent to 36 minutes of brisk walking per day) had a relative risk of 0.45 (95% CI: 0.31, 0.66) compared with non-exercisers. Multivariate adjustment for other risk factors did not substantially alter the association. We observed a positive association between non-work sedentary activity and CHD risk; people with >3.6 hours per day of sedentary activity (for example, television viewing) had an elevated risk of 1.88 (95% CI: 1.09, 3.20) compared with <70 minutes per day in multivariate analysis.


CONCLUSIONS
Leisure-time exercise, including as much as 35-40 minutes per day of brisk walking, was protective for CHD risk and sedentary lifestyles were positively associated with risk of CHD. Given limited resources for care of CHD in India and the important role of physical exercise in disease risk in urban India, improvements in physical activity should be promoted.
Rastogi
Tanuja
T
Department of Nutrition, Harvard School of Public Health, Boston, MA, USA. trastogi@post.harvard.edu
Vaz
Mario
M
Spiegelman
Donna
D
Reddy
K Srinath
KS
Bharathi
A V
AV
Stampfer
Meir J
MJ
Willett
Walter C
WC
Ascherio
Alberto
A
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003327:Coronary Disease / Q000453:epidemiology / Q000517:prevention & control*; D003906:Developing Countries; D004651:Employment; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012306:Risk