P0615Effectiveness of Montelukast Combined with Corticosteroids Versus Corticosteroids Alone in Ulcerative Colitis: A Retrospective Cohort Study.

Background Montelukast, a leukotriene receptor antagonist commonly used in asthma management, has shown potential anti-inflammatory effects in gastrointestinal disorders. However, its role in ulcerative colitis (UC) management remains unclear. This study aimed to compare the effectiveness and safety of montelukast in combination with corticosteroids versus corticosteroids alone in patients with UC. Methods This retrospective cohort study utilized data from the global TriNetX Collaborative Network to evaluate patients diagnosed with ulcerative colitis (UC) between January 1, 2014, and December 31, 2023. Patients were stratified based on exposure to either montelukast in combination with corticosteroids or corticosteroids alone. The primary outcome was the incidence of UC flare-ups at 6 months. Secondary outcomes included all-cause mortality, intestinal obstruction, and rectal bleeding. Propensity score matching was employed to balance baseline demographic and clinical characteristics between the two cohorts, ensuring comparability across key variables. Results After propensity score matching, 5,434 patients were included in each group. The overall cohort’s mean ± SD age was 58.3 ± 16.8 years, and the groups were well balanced in terms of demographic characteristics, including race and gender (standardized difference < 0.25). The proportion of female patients was slightly higher in the montelukast-steroid group (64.9%) compared to the steroid-only group (55.7%). The majority of patients were White (76%) and not Hispanic or Latino (approximately 77%) in both cohorts. At 6 months, ulcerative colitis (UC) flare-ups were more frequent in the montelukast-steroid group compared to the steroid-only group (41.3% vs. 34.7%; risk ratio [RR] 1.19, 95% CI: 1.13–1.25; p < 0.0001). In contrast, the mortality rate was significantly lower in the montelukast-steroid group (3.7% vs. 5.6%; RR 0.65, 95% CI: 0.54–0.77; p < 0.0001). The incidence of rectal bleeding was significantly lower in the montelukast-steroid group (4.25% vs. 5.17%; RR 0.82, 95% CI: 0.69–0.97; p = 0.0236). These results suggest that while montelukast use may be associated with an increased risk of UC flare-ups, it appears to offer a protective effect against both all-cause mortality and rectal bleeding over a 6-month follow-up period. Conclusion The addition of montelukast to corticosteroid therapy in patients with UC was associated with an increased risk of disease flare-ups but a significantly reduced risk of all-cause mortality and rectal bleeding at 6 months. These findings suggest a complex therapeutic profile for montelukast in UC and warrant further prospective studies to elucidate its clinical utility. Conflict of interest: Dr. Patel, Om: No conflict of interest Johal, Jashanveer: No conflict of interest Al-Bataineh, Mahmoud: No conflict of interest Hussein, Abdallah: No conflict of interest Schneider, Yecheskel: No conflict of interest Rajab, Islam: No conflict of interest Salem, Ahmed: No conflict of interest Shanti, Ibrahim: No conflict of interest