Association between red cell distribution width to albumin ratio and all-cause mortality in stroke survivors: An observational study

Stroke is a global cerebrovascular disease. This study mainly explores the association between red cell distribution width to albumin ratio (RAR) and all-cause mortality in stroke survivors, which is helpful for the prognostic management of stroke survivors. Using data from the 1999 to 2018 National Health and Nutrition Examination Survey, Cox regression, restricted cubic spline analysis, receiver operating characteristic curve, and subgroup analysis were applied to assess the relationship between RAR and all-cause mortality in stroke survivors. Sensitivity analysis was also conducted to ensure the robustness of the findings. A total of 1838 stroke survivors were included, with 861 deaths recorded over a median follow-up of 6.42 years. A nonlinear relationship was observed between RAR and all-cause mortality. When RAR was <4.24, it was significantly positively associated with all-cause mortality (hazard ratio = 2.16, 95% confidence interval: 1.77-2.64). In the fully adjusted multivariable model, stroke survivors in the highest quartile of RAR (Q4) had a 1.95 times higher risk of all-cause mortality compared to those in the lowest quartile (Q1). Receiver operating characteristic analysis demonstrated that RAR had good predictive value for all-cause mortality (area under the curve > 0.6). Subgroup analysis showed that there were significant interaction effects between RAR and all-cause mortality in stroke survivors across gender, race, and educational level. Elevated RAR is closely associated with increased all-cause mortality in stroke survivors. This marker may serve as a reliable prognostic indicator for stroke survivors.