Remnant cholesterol associated with all-cause mortality in oldest-old acute coronary syndrome patients: a cohort study

BackgroundPrevious studies showed that remnant cholesterol(RC) partially explained the residual risk of cardiovascular disease. We tried to test the hypothesis that remnant cholesterol is a risk factor for all-cause mortality in oldest-old(>80 years old) patients with acute coronary syndrome(ACS). Methods662 oldest-old patients with acute coronary syndrome and undergoing coronary angiography were finally included in our study. Remnant cholesterol(RC) was calculated by fasting total cholesterol(TC) minus low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C). Multivariable Cox regression analysis was used to identify the association between RC and all-cause mortality. Receiver operating characteristic(ROC) curve was used to compare the discrimination capacity of RC, TC, HDL-C and LDL-C to predict all-cause mortality. ResultsAmong the 662 oldest-old patients enrolled, 92.90% accepted statin therapy. The average age was 81.87 {+/-} 2.14 years old. In the fully-adjusted Cox regression model, the Hazard ratio(HR) [95% confidence interval (CI)] of all-cause mortality was 1.17 (1.01, 1.36) for each standard deviation(SD) increase in RC. Compared to tertile 1, tertile 3 was associated with a 130% increased risk of all-cause mortality (HR:2.30;95%CI:1.45, 3.63). The increased risk of death from tertile 1 to tertile 3 was statistically significant (P for trend<0.001). The subgroup analysis confirmed the significant association between RC and all-cause mortality. ROC curve showed that RC had a better discrimination capacity at predicting all-cause mortality and improved the prognostic value of the Gensini score combined with left ventricular ejection fraction(LVEF). ConclusionRemnant cholesterol was associated with all-cause mortality in oldest-old patients with ACS in a long-term follow-up. Key learning pointsO_ST_ABSWhat is already knownC_ST_ABS(1) Remnant cholesterol was a risk factor for atherosclerotic cardiovascular disease(ASCVD); (2) Emerging studies reported that RC was associated with all-cause mortality in general population, patients with disease status including ischemic heart disease(IHD), heart failure(HF) and metabolic dysfunction-associated fatty liver disease(MAFLD) or patients receiving special treatment such as peritoneal dialysis(PD) and kidney transplantation; (3) However, some studies found that there was no correlation between RC and all-cause mortality. What this study adds(1) We focused on oldest-old ACS patients who underwent angiography and found that RC was associated with all-cause mortality in this special population; (2) The correlation between RC and all-cause mortality was dose-response; (3) RC had a better discrimination capacity at predicting all-cause mortality and improved the prognostic value of the Gensini score combined with LVEF.