Abstract 3596: Obesity as compared with physical inactivity in predicting risk of coronary heart disease and relative association of C- Reactive Protein; The EPIC-Norfolk Prospective Population Study
OBJECTIVE: We assessed the hypothesis that obesity and physical inactivity are independently associated with risk of coronary heart disease (CHD) and explored the comparative importance of C- Reactive Protein (CRP) among habitual (work-related and leisure time) physical activity and obesity.
METHODS: We performed a nested case-control study among 3,305 apparently healthy men and women enrolled in the EPIC-Norfolk prospective population study. The analyses were done by conditional logistic regression, accounting for matching for sex, age and additionally controlling for hormone therapy use, and smoking (current, past never) for risk of CHD and linear regression (adjusted for the same variables) for log-transformed (ln) CRP levels with increasing categories of body mass index (BMI) and physical inactivity.
RESULTS: We found that ln-CRP increased with increasing BMI categories (regression coefficient ß= 0.61, 95%CI 0.51– 0.70, p<0.001) and decreasing activity categories (ß= 0.24, 95%CI 0.14 – 0.34, p<0.001). In joint analyses of BMI and physical activity (figure⇓) ß were significantly higher across both increasing BMI and decreasing activity categories (p<0.001). Compared to physically active participants with healthy weight, the odds ratio for future CHD was 2.81 (95%CI 1.81– 4.35) for inactive and obese participants. The results were slightly attenuated when additionally controlled for CRP (figure⇓).
CONCLUSIONS: In conclusion obesity and physical inactivity independently contribute to the development of CHD. CRP is independently associated with both obesity and physical inactivity and may be one way by which both obesity and inactivity impart higher risk for CHD.