Physical activity, abdominal obesity and the risk of coronary heart disease: a Korean national sample study.

OBJECTIVES: To examine the interaction between physical activity and abdominal obesity in relation to the Framingham Risk Score (FRS) for predicting the 10-year risk of coronary heart disease (CHD) using a representative sample of Korean adults.

STUDY DESIGN: Cross-sectional study.

METHODS: Drawing from the 2007 Korean National Health and Nutrition Examination Survey (NHANES IV-1), data from 2112 adults aged 30-74 years were analysed. The risk of CHD was calculated according to the FRS, and odds ratios (ORs) were analysed for the at-risk group (probability > 10%) with multivariate logistic regression.

RESULTS: Compared with physically active men with a normal waist circumference (WC), inactive men with a large WC had an OR for CHD risk of 2.91 [95% confidence interval (CI) 1.63-5.22]. Compared with active women with a normal WC, inactive women with a large WC had an OR of 6.37 (95% CI 3.44-11.80). Among women with a normal WC, inactive women were at increased risk of CHD compared with active women (OR 2.16, 95% CI 1.19-3.93). Among active individuals, both men and women with large WCs were at increased risk of CHD compared with those with normal WCs.

CONCLUSIONS: Abdominal obesity was associated with risk of CHD regardless of the level of physical activity. The 10-year risk of CHD associated with physical inactivity and abdominal obesity was much stronger in Korean women than in Korean men. While the importance of obesity control and physical activity is clear, future interventions should incorporate more targeted abdominal obesity prevention and control efforts, especially for women.