Association and its population heterogeneities between low-density lipoprotein cholesterol and all-cause and cardiovascular mortality: A population-based cohort study

Abstract

Abstract Background: The association and its population heterogeneities between low-density lipoprotein cholesterol (LDL-C) and all-cause and cardiovascular mortality remain unknown. We aimed to examine the dose-dependent associations of LDL-C levels with specific types of cardiovascular disease (CVD) mortality and heterogeneities in the associations among different population subgroups. Methods: A total of 2,968,462 participants aged 35–75 years from China Health Evaluation And risk Reduction through nationwide Teamwork (ChinaHEART) (2014–2019) were included. Cox proportional hazard models and Fine–Gray subdistribution hazard models were used to estimate associations between LDL-C categories (<70.0, 70.0–99.9, 100.0–129.9 [reference group], 130.0–159.9, 160.0–189.9, and ≥190.0 mg/dL) and all-cause and cause-specific mortality. Results: During a median follow-up of 3.7 years, 57,391 and 23,241 deaths from all-cause and overall CVD were documented. We observed J-shaped associations between LDL-C and death from all-cause, overall CVD, coronary heart disease (CHD), and ischemic stroke, and an L-shaped association between LDL-C and hemorrhagic stroke (HS) mortality (P for non-linearity <0.001). Compared with the reference group (100.0–129.9 mg/dL), very low LDL-C levels (<70.0 mg/dL) were significantly associated with increased risk of overall CVD (hazard ratio [HR]: 1.10, 95% confidence interval [CI]: 1.06–1.14) and HS mortality (HR: 1.37, 95% CI: 1.29–1.45). Very high LDL-C levels (≥190.0 mg/dL) were associated with increased risk of overall CVD (HR: 1.51, 95% CI: 1.40–1.62) and CHD mortality (HR: 2.08, 95% CI: 1.92–2.24). The stronger associations of very low LDL-C with risk of CVD mortality were observed in individuals with older age, low or normal body mass index, low or moderate 10-year atherosclerotic CVD risk, and those without diagnosed CVD or taking statins. Stronger associations between very high LDL-C levels and all-cause and CVD mortality were observed in younger people. Conclusions: People with very low LDL-C had a higher risk of all-cause, CVD, and HS mortality; those with very high LDL-C had a higher risk of all-cause, CVD, and CHD mortality. On the basis of our findings, comprehensive health assessment is needed to evaluate cardiovascular risk and implement appropriate lipid-lowering therapy for people with very low LDL-C.