Impact of Low-density Lipoprotein Cholesterol Levels on Cardiovascular Risk in Chronic Kidney Disease: A Stage-specific Analysis.

BACKGROUND: Lipid management differs between patients with chronic kidney disease and other high-risk populations due to less established association between low-density lipoprotein cholesterol (LDL-C) and cardiovascular events and unclear benefits of statin in chronic kidney disease. We aimed to investigate the association between LDL-C levels and cardiovascular risk stratified by kidney function. METHODS: Using Korean National Health Insurance Service database, we conducted a population-based cohort study including 4,418,485 patients without cardiovascular disease history who underwent health screenings in 2012. Participants were categorized into three groups based on kidney function and five groups according to LDL-C levels. The primary outcomes were myocardial infarction, ischemic stroke, coronary revascularization, and cardiovascular death. RESULTS: Over a mean follow-up of 10.1 years, 80,642 myocardial infarctions, 88,833 strokes, 60,884 coronary revascularizations, and 25,256 cardiovascular deaths occurred. In the chronic kidney disease group, LDL-C levels ≥100 mg/dL were significantly associated with increased composite cardiovascular event risk compared with <70 mg/dL; however, this adjusted association was observed in the end-stage kidney disease group. The 5-year absolute risk increased with LDL-C levels and was further intensified by chronic kidney disease stage progression. Different LDL-C thresholds for cardiovascular risk were identified according to chronic kidney disease stage. Subgroup analyses showed that older age, male sex, and the presence of hypertension, diabetes, or proteinuria strengthened the association between LDL-C and cardiovascular events. CONCLUSIONS: High LDL-C levels were associated with increased cardiovascular risk in patients with chronic kidney disease but not in patients with end-stage kidney disease after multivariable adjustment. Stage-specific LDL-C targets are needed to optimize cardiovascular risk management in chronic kidney disease.