Association Between Red Blood Cell Distribution Width-to-Albumin Ratio and Prognosis of Patients with Aortic Aneurysms

Objective: Red blood cell distribution width (RDW) is a predictor of adverse outcomes in aortic aneurysms. Recent recommendations suggest that combining RDW with other biomarkers could yield better results. We, therefore, propose evaluating the biomarker of vascular aging, albumin with RDW to predict the risk of aortic aneurysms. This study aims to explore whether the combination of RDW with albumin can effectively predict the prognosis of aortic aneurysm patients. Methods: This retrospective cohort study was conducted among adults (age >18) with aortic aneurysms in the Medical Information Mart for Intensive Care Database III V1.4 (MIMIC III). RAR was measured according to the red blood cell distribution width and albumin. The primary outcome was the 30-day mortality rate, and the secondary outcome was the 90-day and one-year mortality rates. Estimation of hazard ratios (HR) was obtained from Cox regression models for all-cause mortality related to red cell distribution width-to-albumin ratio (RAR) values. Results: In total, 312 patients were involved, with an average age of 74.9 +/- 10.9 years and an average RAR value of 5.4 +/- 1.6 mL/g. In 30 days for all-cause mortality, the HR (95% CI) in the highest RAR group (>5.8 mL/g) in tertiles was 2.54 (1.25, 5.14) in the unadjusted model, with a significant difference compared with the reference group (P < 0.05). After adjusting for race, gender and age, there was still a correlation (P < 0.05), and the HR (95% CI) was 2.51 (1.23, 5.10). Further adjustment of possible covariates showed similar correlation in model 3 (P < 0.05), and HR (95% CI) was 2.66 (1.17, 6.01). Multivariable logistic regression shows that RAR is an independent risk factor for the outcome of aortic aneurysms after adjusting the covariates. In the subgroup analysis, we analyzed the patient's complications, and no significant interaction was observed. Conclusion: RAR is a risk factor for patients with aortic aneurysms. However, more indepth research is warranted to further analyze and substantiate our findings on the role of RAR in aortic aneurysm patients.