Association of red blood cell distribution width-to-albumin ratio with mortality in patients undergoing transcatheter aortic valve replacement

Abstract

BackgroundFrailty is associated with poor prognosis in patients undergoing transcatheter aortic valve replacement (TAVR). The red blood cell distribution width (RDW)-to-albumin ratio (RAR) reflects key components of frailty. This study aimed to evaluate the relationship between RAR and all-cause mortality in patients undergoing TAVR.MethodsThe data were extracted from the Medical Information Mart for Intensive Care IV database. The RAR was computed by dividing the RDW by the albumin. The primary outcome was all-cause mortality within 1-year following TAVR. The association between RAR and the primary outcome was evaluated using the Kaplan-Meier survival curves, restricted cubic spline (RCS), and Cox proportional hazard regression models.ResultsA total of 760 patients (52.9% male) with a median age of 84.0 years were assessed. The Kaplan-Meier survival curves showed that patients with higher RAR had higher mortality (log-rankP <0.001). After adjustment for potential confounders, we found that a 1 unit increase in RAR was associated with a 46% increase in 1-year mortality (HR = 1.46, 95% CI:1.22–1.75,P< 0.001). According to the RAR tertiles, high RAR (RAR > 4.0) compared with the low RAR group (RAR < 3.5) significantly increased the risk of 1-year mortality (HR = 2.21, 95% CI: 1.23–3.95,P= 0.008). The RCS regression model revealed a continuous linear relationship between RAR and all-cause mortality. No significant interaction was observed in the subgroup analysis.ConclusionThe RAR is independently associated with all-cause mortality in patients treated with TAVR. The higher the RAR, the higher the mortality. This simple indicator may be helpful for risk stratification of TAVR patients.