Diabetes and cause-specific mortality in a prospective cohort of one million U.S. adults

OBJECTIVE - Diabetes is a major predictor of death from heart disease and stroke; its impact on nonvascular mortality, including specific cancers, is less understood. We examined the association of diabetes with cause-specific mortality, including deaths from specific cancers. RESEARCH DESIGN AND METHODS - A prospective cohort of 1,053,831 U.S. adults, without cancer at baseline, enrolled in the Cancer Prevention Study-II in 1982 and was followed formortality until December 2008. At baseline, participants completed a self-administered questionnaire that included information on diabetes, smoking, physical activity, height, and weight. Multivariable-adjusted relative risks (RRs) (95% CI) were estimated using Cox proportional hazards regression. RESULTS - During 26 years of follow-up, 243,051 men and 222,109 women died. In multivariable models that controlled for age, BMI, and other variables, diabetes was associated with higher risk of all-cause mortality (women RR 1.90 [95% CI 1.87-1.93]; men 1.73 [1.70-1.75]). Among women, diabetes was associated with higher risk of death from cancers of the liver (1.40 [1.05-1.86]), pancreas (1.31 [1.14-1.51]), endometrium(1.33 [1.08-1.65]), colon (1.18 [1.04-1.33]), and breast (1.16 [1.03-1.29]). Among men, diabetes was associated with risk of death from cancers of the breast (4.20 [2.20-8.04]), liver (2.26 [1.89-2.70]), oral cavity and pharynx (1.44 [1.07-1.94]), pancreas (1.40 [1.23-1.59]), bladder (1.22 [1.01-1.47]), colon (1.15 [1.03-1.29]), and (inversely) prostate (0.88 [0.79-0.97]). Diabeteswas also associated with higher risks of death involving the circulatory system, respiratory system, digestive system, genitourinary system, and external causes/accidental deaths. CONCLUSIONS - Diabetes is associated with higher risk of death for many diseases, including several specific forms of cancer.