Red blood cell distribution width to albumin ratio as novel prognostic biomarker in cardiovascular disease

• Published in: European heart journal Vol. 45; no. Supplement_1
• Main Authors: Arba, I F, Multazam, C C Z, Widiarti, W, Siahaan, P P, Oktaviono, Y H, Setyobudi, D, Saputra, P B T
• Format: Journal Article
• Language: English
• Published: 28.10.2024
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1093/eurheartj/ehae666.3741

Abstract Background The red blood cell distribution width-to-albumin ratio (RAR) is a novel, cost-effective, and accessible biomarker for inflammation. Although numerous studies have investigated the relationship between RAR values and mortality in cardiovascular diseases (CVD), the generalizability and robustness of these individual studies' results remain uncertain, underscoring the necessity for a meta-analysis. Purpose To explore the pooled association between RAR and all-cause mortality in several CVDs. Methods A systematic search for eligible studies was conducted across scientific databases, including Scopus, Web of Science, PubMed, and ProQuest, up to February 1, 2024. Mortality hazard ratios (HRs) for the highest versus lowest RAR categories were pooled using the Generic Inverse Variance method. A dose-response meta-analysis was performed using generalized least-squares regression to estimate trends of HRs across dose categories. Publication bias was assessed by inspecting funnel plots and performing Egger's test. Subgroup analyses were based on the underlying CVDs. Statistical analyses were executed in RStudio software, with the significance threshold set at p < 0.05. Results This systematic review and meta-analysis reviewed 16 high-quality studies published between 2021 and 2024 with 30,933 participants. The underlying diseases in the included studies were Acute Myocardial Infarction (AMI), Heart Failure (HF), Atrial Fibrillation (AF), aortic valvular disease, stroke and pulmonary embolism. The lowest quartile range for RAR was 0.80–1.20 ml/g, while the highest quartile ranged from 6.09 to 15.45 ml/g. Pooled results with a random-effect model showed that patients with higher RAR had significantly increased risk of all-cause mortality (HR 1.88, 95%CI 1.59–2.23, p<0.0001, I² = 91%). Non-linearity was observed in the dose-response relationship; thus, it was primarily illustrated using the restricted cubic spline model, with the linear model provided for comparison. A 1 ml/g increase in RAR corresponded to a 27% rise in the predicted HR for all-cause mortality (HR 1.27, 95%CI 1.16–1.39; p < 0.0001). Subgroup analyses based on the primary CVD diagnoses in the included studies confirmed a significant association between RAR values and all-cause mortality across all subgroups (AMI: HR 2.43, 95%CI 1.52–3.87, I² = 45%; HF: HR 1.78, 95%CI 1.13–2.81, I² = 94%; Stroke: HR 1.58, 95%CI 0.94–2.67, I² = 90%; Other CVD: HR 1.97, 95%CI 1.34–2.89, I² = 57%; p for interaction 0.24). Conclusion This is the first meta-analysis demonstrating the positive dose-response association between RAR values and all-cause mortality in CVD. Thus, RAR may be considered as a simple and practical prognostic biomarker in CVD.Forest plot based on CVD diagnosisDose-response RAR value to HR