Association of low-density lipoprotein-cholesterol with all-cause and cause-specific mortality.

Aims: To explore the association between low-density lipoprotein-cholesterol (LDL-C) and all-cause and cause-specific mortality based on a prospective cohort study.

Methods: Among 10850 individuals enrolled from National Health and Nutrition Examination Survey (NHANES) 1999-2014, 1355 (12.5%) died after an average follow-up of 5.7 years. Cox proportional regression models were used to determine the association between LDL-C with the risk of mortality.

Results: The level of LDL-C was L-shaped associated with the risk of all-cause mortality, namely a low level was related to an increased mortality risk. The level of LDL-C associated with the lowest risk of all-cause mortality was 124 mg/dL (3.2 mmol/L) in the overall population, and 134 mg/dL (3.4 mmol/L) in individuals not receiving lipid lowering treatment. Compared with participants with LDL-C of 110-134 mg/dL (2.8-3.5 mmol/L), the multivariable adjusted hazard ratio was 1.18 (95% confidence interval 1.01 to 1.38) for individuals with the lowest quartile for all-cause mortality. In participants with coronary heart diseases, the conclusion was similar but the critical point was lower.

Conclusions: We found that low levels of LDL-C increased the risk of all-cause mortality, and the lowest risk of all-cause mortality for LDL-C concentration was 124 mg/dL (3.2 mmol/L). Our results provide a reasonable range of LDL-C when to initiate a statin therapy in clinical practice.