A U-shaped association between the LDL-cholesterol to HDL-cholesterol ratio and all-cause mortality in elderly hypertensive patients: a prospective cohort study

BACKGROUND: The low-density lipoprotein cholesterol/high-density lipoprotein- cholesterol (LDL-C/HDL-C) ratio is an excellent predictor of cardiovascular disease (CVD). However, previous studies linking the LDL-C/HDL-C ratio to mortality have yielded inconsistent results and been limited by short follow-up periods. Therefore, the aim of the present study was to determine whether the LDL-C/HDL-C ratio could be an effective predictor of all-cause mortality in elderly hypertensive patients. METHODS: A total of 6941 hypertensive patients aged 65 years or older who were not treated with lipid-lowering drugs were selected from the Chinese Hypertension Registry for analysis. The endpoint of the study was all-cause mortality. The relationship between the LDL-C/HDL-C ratio and all-cause mortality was determined using multivariate Cox proportional hazards regression, smoothing curve fitting (penalized spline method), subgroup analysis and Kaplan–Meier survival curve analysis. RESULTS: During a median follow-up of 1.72 years, 157 all-cause deaths occurred. A U-shaped association was found between the LDL-C/HDL-C ratio and all-cause mortality. Patients were divided according to the quintiles of the LDL-C/HDL-C ratio. Compared to the reference group (Q3: 1.67–2.10), patients with both lower (Q1 and Q2) and higher (Q4 and Q5) LDL-C/HDL-C ratios had higher all-cause mortality (< 1.67: HR 1.81, 95% CI: 1.08–3.03; ≥2.10: HR 2.00, 95% CI: 1.18–3.39). Compared with the lower and higher LDL-C/HDL-C ratio groups, patients with LDL-C/HDL-C ratios of 1.67–2.10 had a significantly higher survival probability (log-rank P = 0.038). CONCLUSIONS: The results suggest that there is a U-shaped association between the LDL-C/HDL-C ratio and all-cause mortality. Both lower and higher LDL-C/HDL-C ratios were associated with increased all-cause mortality in elderly hypertensive patients. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12944-020-01413-5.