Uric acid-to-albumin ratio × monocyte-to-lymphocyte ratio is a novel biomarker for predicting all-cause mortality and cardiovascular mortality in patients with ST-segment elevation myocardial infarction

Background Uric acid-to-albumin ratio (UAR) and monocyte-to-lymphocyte ratio (MLR) predict adverse outcomes in cardiovascular disease (CVD). We aim to explore the predictive value of UAR combined with MLR for all-cause and cardiovascular mortality in patients with ST-segment elevation myocardial infarction (STEMI). Methods This retrospective cohort study included 1045 patients with STEMI who had undergone emergency percutaneous coronary intervention (PCI) (2018–2023). Uric acid-to-albumin ratio × monocyte-to-lymphocyte ratio (UAML) was defined as the product of UAR and MLR. Mortality prediction was evaluated via Kaplan–Meier, Cox regression, and time-dependent receiver operating characteristic (ROC) analyses. Results Stratifying 1045 patients with STEMI by median UAML (3.35) revealed significantly higher cumulative all-cause mortality (log-rank χ 2 =41.114, P < 0.001) and cardiovascular mortality ( χ 2 = 32.153, P < 0.001) in the high-UAML (≥3.35) vs. low-UAML (<3.35) group. Multivariate Cox analysis confirmed UAML as an independent predictor of all-cause mortality [hazard ratio (HR) = 2.217, 95% confidence interval (CI): 1.399–3.514; P < 0.001] and cardiovascular mortality (HR = 2.160, 95% CI: 1.267–3.618; P = 0.005). Time-dependent ROC demonstrated superior predictive discrimination for UAML over individual components in both all-cause mortality [area under the ROC curve (AUC) = 0.704 vs. UAR = 0.686/MLR = 0.627] and cardiovascular mortality (AUC = 0.700 vs. 0.690/0.615). Conclusion UAML may serve as a strong prognostic factor for all-cause and cardiovascular mortality in patients with STEMI who undergo emergency PCI, and UAML has a stronger predictive value than UAR or MLR.