Remnant cholesterol and the risk of cardiovascular disease in type 2 diabetes: a nationwide longitudinal cohort study

BACKGROUND: Elevated remnant cholesterol (remnant-C) is considered a risk factor for cardiovascular disease (CVD); however, whether this notion applies to the East Asian population with type 2 diabetes (T2D) has not been established. This study investigated the association between remnant-C concentrations and the risk of CVD in Korean patients with T2D. METHODS: By using the Korean National Health Insurance Service database, 1,956,452 patients with T2D and without atherosclerotic CVD who underwent regular health checks between 2009 and 2012 were included. Cox regression analyses were conducted to assess the association between remnant-C concentrations and incident CVD comprising myocardial infarction (MI) and ischemic stroke. RESULTS: In total, 50,120 (2.56%) cases of MI and 73,231 (3.74%) cases of ischemic strokes occurred during a median follow-up of 8.1 years. The adjusted hazard ratios for MI and stroke in the highest remnant-C quartile were 1.281 (95% confidence interval [CIs], 1.249–1.314) for MI and 1.22 (1.195–1.247) for ischemic stroke, compared to those in the lowest quartiles. The results were similar, based on stratified analysis by age, sex, use of statin or fibrate, and levels of other cholesterol. The increased risk of CVD in the highest remnant-C quartile was profound in patients who had a longer T2D duration. A remnant-C concentration ≥ 30 mg/dL differentiated patients who were at a higher risk of CVD, compared to patients with a lower concentrations, regardless of whether LDL-C levels were or were not on target at ≤ 100 mg/dL. CONCLUSION: In Korean patients with T2D, remnant-C was associated with CVD, independent of the LDL-C level or other conventional CVD risk factors. Our finding confirmed evidence of the causal role of remnant-C on CVD, as a residual risk of CVD, in East Asian patients with T2D. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12933-022-01667-6.