Prognostic value of monocyte-to-high-density lipoprotein-cholesterol ratio for all-cause mortality and heart failure in new-onset atrial fibrillation: a population-based cohort study

Abstract

Abstract Background A growing body of evidence suggests that inflammation plays a role in the onset and progression of atrial fibrillation (AF). Monocyte-to-high-density lipoprotein-cholesterol ratio (MHR) has emerged as a novel and accessible biomarker that reflects both inflammation and oxidative stress. Previous studies have demonstrated the predictive value of MHR in several cardiovascular diseases including ischaemic stroke and acute coronary syndrome, but the association between MHR and adverse outcomes of AF remains unclear. Purpose With this study, we aimed to investigate the relationship of MHR with all-cause mortality and incident heart failure in patients with new-onset AF. Methods Patients with newly diagnosed AF from 1998-2021 (n=80,911) were included in this Hong Kong population-based cohort study. MHR was obtained by dividing fasting monocyte count by high-density lipoprotein-cholesterol, and patients were grouped according to MHR tertiles. We followed up patients until occurrence of outcomes, death or 1st September, 2022. The primary outcome was all-cause mortality, and the secondary outcome was incident heart failure. We evaluated the associations of MHR with all-cause mortality and heart failure both on a continuous scale using restricted cubic spline curves and by categories using multivariate Cox proportional hazards regression model. Results The median age of the cohort was 77.9 years old and 41,536 (51.3%) were male. Over a median follow-up of 3.7 years, 43,902 (54.3%) deaths and 14,114 (17.4%) incident heart failure occurred. The restricted cubic spline curves illustrated that MHR had a non-linear association with all-cause mortality and heart failure. Univariate Cox regression indicated that increased MHR at tertiles 2 and 3 were significantly associated with higher risks of all-cause mortality (HR: 1.06 [1.04-1.09], P<0.001, 1.25 [1.22-1.28], P<0.001, respectively) and new onset heart failure (1.07 [1.02-1.11], P=0.002, 1.23 [1.18-1.28], P<0.001, respectively) when compared to those in tertile 1. MHR remained a significant predictor of mortality (tertile 2 HR: 1.06 [1.04-1.09], P<0.001, tertile 3 HR: 1.22 [1.19-1.25], P<0.001) and heart failure (tertile 2 HR: 1.06 [1.02-1.10], P=0.007, tertile 3 HR: 1.21 [1.16-1.26], P<0.001) after multivariable adjustment. Conclusion MHR is a promising prognostic biomarker for all-cause mortality and heart failure in patients with new-onset AF.