Association between red cell distribution width-to-albumin ratio and acute kidney injury in acute pancreatitis: A retrospective cohort study from the MIMIC-IV database

This study aimed to evaluate the association between the red cell distribution width-to-albumin ratio (RAR) and the early onset of Acute Kidney Injury (AKI) in patients diagnosed with acute pancreatitis (AP). A retrospective cohort study was conducted using data from the Medical Information Mart for Intensive Care IV database, focusing on the first 24 hours following admission to the intensive care unit (ICU). The primary outcome was the incidence of AKI within 7 days of ICU admission, as defined by the Kidney Disease: Improving Global Outcomes criteria. Logistic regression models were employed to assess the association, with subgroup analyses considering variables such as age, sex, renal disease, diabetes, sepsis, use of mechanical ventilation, and sequential organ failure assessment scores. The analysis included 599 patients. Each unit increase in RAR was linearly associated with a 62% greater likelihood of AKI within 7 days of ICU admission (odds ratio = 1.62, 95% confidence interval [CI]: 1.34–1.96, P < .010). When RAR was categorized into tertiles, a graded increase in AKI risk was observed. Patients in the middle tertile had a 2.13-fold higher risk of AKI (95% CI: 1.3–3.5, P = .003), while those in the highest tertile demonstrated a 3.64-fold increased risk (95% CI: 2.58–8.33, P < .001) compared to the lowest tertile. The association persisted across all examined subgroups, highlighting the robustness of RAR as a predictive factor for AKI in patients with AP. RAR demonstrated a significant association with the early onset of AKI in patients with AP admitted to the ICU. These findings highlight the potential of RAR as a reliable predictor for AKI in this patient population.