Physical activity and life expectancy with and without diabetes: life table analysis of the Framingham Heart Study

OBJECTIVE: Physical activity is associated with a reduced risk of developing diabetes and with reduced mortality among diabetic patients. However, the effects of physical activity on the number of years lived with and without diabetes are unclear. Our aim is to calculate the differences in life expectancy with and without type 2 diabetes associated with different levels of physical activity. RESEARCH DESIGN AND METHODS: Using data from the Framingham Heart Study, we constructed multistate life tables starting at age 50 years for men and women. Transition rates by level of physical activity were derived for three transitions: nondiabetic to death, nondiabetic to diabetes, and diabetes to death. We used hazard ratios associated with different physical activity levels after adjustment for age, sex, and potential confounders. RESULTS: For men and women with moderate physical activity, life expectancy without diabetes at age 50 years was 2.3 (95% CI 1.2-3.4) years longer than for subjects in the low physical activity group. For men and women with high physical activity, these differences were 4.2 (2.9-5.5) and 4.0 (2.8-5.1) years, respectively. Life expectancy with diabetes was 0.5 (-1.0 to 0.0) and 0.6 (-1.1 to -0.1) years less for moderately active men and women compared with their sedentary counterparts. For high activity, these differences were 0.1 (-0.7 to 0.5) and 0.2 (-0.8 to 0.3) years, respectively. CONCLUSIONS: Moderately and highly active people have a longer total life expectancy and live more years free of diabetes than their sedentary counterparts but do not spend more years with diabetes.