TITLE:
Association between Red Blood Cell Distribution Width-to-Albumin Ratio and All-Cause Mortality in the General Population: A Cohort Study
AUTHORS:
Chunyue Guo, Xingyuan Liu, Xiaoyu Liang, Yun Chang, Wenqing Gao
KEYWORDS:
Red Blood Cell Distribution Width, Albumin, RAR, All-Cause Mortality, Cohort Study
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.14 No.5,
May
29,
2026
ABSTRACT: Background: The red blood cell distribution width (RDW) to albumin ratio (RAR) has emerged as a novel indicator for mortality in patients with various diseases. However, whether RAR is associated with all-cause mortality in the general population remains unknown. This study aims to investigate the relationship between RAR and all-cause mortality and to elucidate their dose-response association. Methods: Data were derived from the National Health and Nutrition Examination (NHANES) Survey (1998-2018). The RAR was calculated by dividing RDW (%) by the albumin concentration (g/dL). The primary outcome was all-cause mortality, which was linked to the National Death Index (NDI) database through December 31, 2019. Potential associations between RAR and the risk of all-cause mortality were assessed using Cox proportional hazards regression models. Restricted cubic spline regressions were applied to examine possible nonlinear associations. Subgroup analyses were conducted to evaluate the robustness of these associations. Results: A total of 30840 participants aged 18 years old and above, of whom 48.48% were male, were included in the study. The multivariate-adjusted HR (95% CI) for all-cause mortality was 1.00 (reference), 2.03 (1.82 - 2.26), 3.29 (2.96 - 3.66), and 5.04 (4.54 - 5.59) across the RAR quartiles (Q1, Q2, Q3, and Q4, respectively) ( P P for overall test P ? for nonlinearity P Conclusions: In this cohort study, RAR is independently associated with all-cause mortality in the US general population, with a nonlinear positive dose-response relationship. These findings suggest that RAR may be a simple, reliable, and inexpensive indicator for identifying individuals at high risk of mortality in clinical practice.