Favourable changes in mortality in people with diabetes: US NHANES 1999–2010

AIMS Diabetes-related complications have declined during the past two decades. We aimed to examine whether mortality in people with diabetes improved over time in the 1999 to 2010 National Health and Nutrition Examination Survey (NHANES). METHODS We conducted a prospective cohort study using 1999 to 2004 and 2005 to 2010 data from the NHANES. For primary analyses, we compared the unadjusted, age-adjusted and multivariable-adjusted hazard ratios (HR) for mortality outcomes (total, cardiovascular, cardiac and cancer deaths) of the participants with diabetes with those without diabetes using Cox proportional hazard models. RESULTS For each mortality outcome, HR (95% confidence interval) in diabetic participants during the period 2005 to 2010 was lower than that during the period 1999 to 2004 (all-cause death, 2.76 [1.87-4.08] vs 4.23 [2.57-6.98]; cardiovascular death, 2.70 [1.20-6.04] vs 8.82 [3.28-23.70]; cardiac death, 2.45 [0.98-6.09] vs 15.55 [7.01-34.50]; cancer death, 2.33 [0.87-6.23] vs 3.03 [1.20-7.65]). Compared with mortality outcome during the period 1999 to 2004, greater declines in mortality during the period 2005 to 2010 were observed for cardiovascular (-54.0%) and cardiac deaths (-64.8%). In age-adjusted and multivariable-adjusted models, the cumulative event rates for total, cardiovascular and cardiac deaths were not significantly different between participants with and without diabetes during the period 2005-2010; this was not the case during the period 1999-2004. The leading cause of death was malignant neoplasm during the period 2005-2010. CONCLUSION Considerably improved outcomes for total, cardiovascular and cardiac deaths were observed in people with diabetes during the 2005 to 2010 NHANES compared to the 1999 to 2004 NHANES.