Coronary artery disease risk prediction by combined stratification of low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol levels across different glucose statuses

Aim: To investigate the association between low-density lipoprotein-cholesterol (LDL-C) levels and coronary artery disease (CAD) incidence based on combining high-density lipoprotein-cholesterol (HDL-C) levels and glucose status. Materials and Methods: In this retrospective cohort study, we used data from a nationwide claims database (1,524,289 individuals without a history of CAD or familial hypercholesterolaemia; 2008-2019). Cox proportional hazards modelling identified the risk of incident CAD by a novel combination of four HDL-C levels, seven LDL-C levels and glucose status. Results: During the follow-up period (mean: 5.5 years), 8301 (0.99/1000 person-years) events occurred. The risk of CAD increased from lower LDL-C levels accompanied by lower HDL-C levels regardless of the glucose status. Using the most favourable levels of HDL-C and LDL-C (i.e. 60-99 mg/dL and <80 mg/dL, respectively) as references, the hazard ratios (95% confidence interval) for the group with HDL-C levels <40 mg/dL and LDL-C levels <80 mg/dL were 2.74 (1.47-5.11), 2.52 (1.30-4.91) and 2.85 (1.68-4.84) for normoglycaemia, borderline glycaemia and diabetes, respectively. Comparison of the most favourable levels of HDL-C and LDL-C with their least favourable levels (i.e. <40 mg/dL and 180-199 mg/dL, respectively) revealed that the risk of new-onset CAD exhibited a 19-, nine- and seven-fold increase in individuals with normoglycaemia, borderline glycaemia and diabetes, respectively. Conclusions: To prevent CAD, LDL-C levels should be strictly controlled in patients with low HDL-C levels regardless of glucose tolerance. Individualized treatment, which involves setting target LDL-C levels based on glucose tolerance and HDL-C values, is required.