Abstract
BACKGROUND: The excess risks of mortality and cardiovascular morbidity among patients with type 2 diabetes mellitus (T2DM) is well known. In this nationwide study, we assessed risks of mortality and cardiovascular events comparing patients with T2DM and matched controls. METHODS: We identified patients with T2DM in a retrospective cohort study using the database of the National Health Insurance Fund between 1 January 2010 and 31 December, 2013. Controls were randomly included and matched according to age, gender, and zip code of residence. Patients were divided into subgroups according to age decades for outcome analyses. RESULTS: During the mean follow-up period of 2.3 years, 152,678 patients with T2DM and 305,356 matched controls were included. Patients with T2DM showed significantly higher risk for all-cause mortality (HR 1.26, 95% CI 1.22-1.29, p < 0.0001), myocardial infarction (HR 1.81, 95% CI 1.69-1.94, p < 0.0001) and stroke (HR 1.40, 95% CI 1.35-1.46, p < 0.0001) compared to matched controls. The higher risk associated with T2DM for mortality, myocardial infarction and stroke differed significantly between age groups (p(interaction) < 0.05 for all outcomes) with significantly higher risk observed in younger patients. CONCLUSIONS: The risk of cardiovascular outcomes and all-cause mortality is significantly higher in patients with T2DM. Notably, the relative hazard increases with decreasing age suggesting that younger patients with T2DM should receive more attention for cardiovascular prevention.