Sex differences in LMR ratio and coronary artery stenosis severity among patients with coronary artery disease

Background Previous studies have indicated that the lymphocyte-to-monocyte ratio (LMR) is associated with the severity of coronary artery disease (CAD). However, whether this association differs between sexes remains unclear. This study aimed to evaluate the association between LMR and Gensini score in patients with CAD, with a focus on potential sex differences. Methods A total of 1,673 patients undergoing coronary angiography were included. The severity of CAD was assessed using the Gensini score, and patients were categorized into three groups based on Gensini score tertiles: T1 (≤10), T2 (>10 to <44), and T3 (≥44). Sex-stratified analyses and multivariable regression models were employed to assess the association between LMR and CAD severity. Results LMR was significantly lower in patients with higher Gensini scores ( P < 0.001). After multivariable adjustment, LMR was independently and inversely associated with the Gensini score in the overall population. A significant sex–LMR interaction was observed ( P < 0.05). In sex-stratified analyses, the inverse association between LMR and Gensini score was stronger in females than in males. Conclusion LMR is independently and inversely associated with the severity of CAD, with a stronger association observed in female patients. These findings suggest that LMR may serve as a potential inflammatory marker for assessing CAD severity, and its clinical relevance may differ between sexes.