Association between monocyte-to-high-density lipoprotein cholesterol ratio and all-cause mortality in stroke patients: Exploring the potential mediating role of serum creatinine in a NHANES-based study

Identifying reliable prognostic biomarkers is crucial for the effective management of stroke patients. The monocyte-to-high-density lipoprotein cholesterol ratio (MHR), calculated as the ratio of blood monocyte count to high-density lipoprotein levels, is commonly used to assess the relationship between inflammation and cardiovascular or cerebrovascular health. MHR may play an important role in the prognostic management of stroke. This study aimed to investigate the association between MHR and all-cause mortality in patients with stroke. This was a retrospective observational study using data from the National Health and Nutrition Examination Survey in the United States. A restricted cubic spline analysis was conducted to visualize the relationship between MHR and the risk of all-cause mortality among stroke patients. Weighted Cox proportional hazards models were employed to assess the independent association between MHR and all-cause mortality. Mediation analysis was performed to explore the indirect effect of MHR on mortality through serum creatinine (Cr). A total of 1513 patients were included in the study, of whom 614 died and 899 survived. Restricted cubic spline analysis revealed a positive association between MHR and all-cause mortality in stroke patients. Patients were categorized into a high MHR group (>0.47) and a low MHR group (≤0.47). After adjusting for relevant covariates, the weighted Cox model showed that patients in the high MHR group had a significantly increased risk of all-cause mortality (HR: 1.172, 95% CI: 1.04-1.32, P = .009). Stratified and interaction analyses confirmed the stability of the core findings. Mediation analysis indicated that Cr partially mediated the association between MHR and all-cause mortality in stroke patients, accounting for 10.81% of the total effect. Elevated MHR is associated with a higher risk of all-cause mortality in stroke patients, and this relationship is partly mediated by Cr, underscoring the potential importance of renal function in modulating inflammation-related mortality risk.