Risk of early mortality and cardiovascular disease according to the presence of recently diagnosed diabetes and requirement for insulin treatment: A nationwide study

AIMS/INTRODUCTION: We estimated the hazards of cardiovascular diseases (CVDs) and early all‐cause mortality in Korean adults according to the presence of recently diagnosed type 2 diabetes (type 2 diabetes for <5 years) and insulin use. MATERIALS AND METHODS: We used the Korean National Health Insurance Service–National Sample Cohort database (2002–2015) for this longitudinal population‐based study. Among adults aged ≥40 years without baseline CVD, individuals without diabetes or with recently diagnosed type 2 diabetes were selected (N = 363,919). The hazard ratios (HRs) for myocardial infarction (MI), stroke, and all‐cause mortality during follow‐up were analyzed according to three groups categorized by the presence of type 2 diabetes and insulin use. RESULTS: Within a mean 7.8 years, there were 5,275 MIs, 7,220 strokes, and 15,834 deaths. The hazards for outcomes were higher in the insulin‐treated type 2 diabetes group than in the non‐diabetes group [HR (95% CI): 2.344 (1.870–2.938) for MI, 2.420 (1.993–2.937) for stroke, and 3.037 (2.706–3.407) for death], higher in the non‐insulin‐treated type 2 diabetes group than in the non‐diabetes group [HR (95% CI): 1.284 (1.159–1.423) for MI, 1.435 (1.320–1.561) for stroke, and 1.135 (1.067–1.206) for death], and higher in the insulin‐treated type 2 diabetes group than in the non‐insulin‐treated type 2 diabetes group [HR (95% CI): 1.914 (1.502–2.441) for MI, 1.676 (1.363–2.060) for stroke, and 2.535 (2.232–2.880) for death]. CONCLUSIONS: Recently diagnosed type 2 diabetes patients showed increased risks of incident CVDs and premature mortality, and insulin‐treated group demonstrated an additional increase in the risks of these outcomes in adults with recently diagnosed type 2 diabetes, suggesting the need for intensified cardio‐protective interventions for adults with insulin‐treated type 2 diabetes.