Lymphocyte-to-monocyte ratio is a short-term predictive marker of ulcerative colitis after induction of advanced therapy

Advanced therapies for patients with mild-to-severe ulcerative colitis (UC) may result in treatment failure. We examined whether the lymphocyte-to-monocyte ratio (L/M ratio) could predict the failure of advanced therapies. This retrospective, observational, cohort study included 73 patients who were treated with advanced therapies at the Hamamatsu University School of Medicine (Shizuoka, Japan) between February 2011 and November 2020. The patients were divided into the non-failure and failure groups, and their leukocyte counts and ratios before induction were examined. Univariate and multivariate analyses were performed to identify the prognostic factors. Advanced therapies failed within 3 months in 15 (20.5%) patients. Only the L/M ratio was significantly lower in the failure group than in the non-failure group (P = 0.004). Receiver-operating characteristic (ROC) curve analysis revealed that an L/M ratio of <= 3.417 was predictive of treatment failure; the area under the curve (AUC) was 0.747 (95% CI, 0.620-0.874). Kaplan-Meier analysis revealed that the failure-free rate was significantly lower in the group with an L/M ratio of <= 3.417 than in the group with an L/M ratio of >3.417 (log-rank test P = 0.002). Cox proportional hazard regression analysis identified an L/M ratio of <= 3.417 as an independent risk factor for failure within 3 months after the induction of advanced therapies. Furthermore, ROC analysis of patients who did not receive immunomodulators also revealed that the cut-off L/M ratio was 3.417 and the AUC was 0.796 (95% CI, 0.666-0.925). In patients receiving advanced therapies for active UC, the L/M ratio can predict treatment failure within 3 months. L/M ratios could facilitate the transition from advanced therapies to subsequent treatments.