Combined prognostic value of the monocyte-to-HDL cholesterol ratio and ACEF score in patients with type 2 myocardial infarction: a retrospective cohort study

Background: The monocyte-to-high-density lipoprotein cholesterol ratio (MHR), reflecting inflammation and lipid metabolism, has been associated with adverse cardiovascular outcomes. The ACEF score, derived from age, creatinine, and ejection fraction, is a well-established cardiovascular risk model. However, their prognostic value in patients with type 2 myocardial infarction (T2MI) remains unclear. This study aimed to evaluate the association of MHR and the ACEF score with major adverse cardiovascular and cerebrovascular events (MACCEs) in T2MI patients and assess whether their combination improves risk stratification. Methods: This retrospective cohort study included T2MI patients admitted to Cangzhou People's Hospital from January 2019 to December 2021. Baseline MHR and ACEF scores were calculated. The primary endpoint was 3-year MACCEs, including all-cause death, nonfatal myocardial infarction, revascularization, non-fatal stroke, and readmission for unstable angina or heart failure. Cox regression and restricted cubic splines (RCS) were used to evaluate associations between MHR, ACEF, and MACCEs. ROC curves assessed the discriminative ability of MHR, ACEF, and their combination, with AUC comparisons via DeLong’s test. Risk reclassification was evaluated using IDI and NRI. Decision curve analysis estimated clinical benefit. Kaplan–Meier survival analyses stratified by tertiles, and subgroup analyses were performed. Results: Multivariable Cox regression showed that MHR and ACEF were independent predictors of MACCEs (all P <0.001). Patients with both high MHR and ACEF had the highest risk ( P <0.001). The combined model yielded superior discrimination (AUC=0.798) and significantly improved reclassification (IDI and NRI, all P <0.05). Kaplan–Meier and decision curve analyses confirmed worse survival and greater net benefit in the high-risk group. Subgroup analyses showed consistent results across strata (all P -interaction > 0.05). Conclusion: Both MHR and the ACEF score are independent prognostic markers in patients with T2MI. Their combined improves risk stratification and may assist clinical decision-making.