Prognostic Significance of Red Blood Cell Distribution Width-to-Albumin Ratio in Predicting 1-Year Mortality for Critically Ill Chronic Obstructive Pulmonary Disease Patients.

Background: Chronic obstructive pulmonary disease (COPD) is a major global healthcare challenge. To address the gap in existing prognostic research, this study examined the possibility of the red blood cell distribution width-albumin ratio (RAR) as a viable biomarker for predicting COPD outcomes.

Aims: To evaluate the relationship between RAR and the one-year mortality risk in COPD patients.

Study design: A retrospective cohort study.

Methods: Participants were grouped based on their RAR levels. Multiple interpolations were used to address missing data. The effect of biomarkers on mortality was estimated using Kaplan-Meier survival curves and Cox risk regression models. Stratified analyses were conducted to assess the consistency of the RAR's predictive value for mortality across different subgroups. RAR was used to build a predictive model and the C-index and time-dependent receiver operating characteristic curves were used to evaluate the model's performance.

Results: This study examined 2,379 patients, dividing them into three groups based on their RAR levels. According to Cox regression, RAR was correlated with the 1-year all-cause mortality of patients [model 3: HR = 1.24 (95% confidence interval 1.19-1.29) p < 0.001], with consistent positive correlations between subgroups. This relationship was shown to be linear via the restricted cubic spline. RAR had been demonstrated to be a potentially more effective biomarker than albumin and red blood cell distribution width for determining the one-year mortality risk in COPD patients.

Conclusion: A significant association was found between RAR and the one-year mortality of COPD patients. This result implies that RAR may be an effective instrument for determining the prognosis in COPD patients.