Similar Efficacy of Mesalazine in Adult and Older Adult Ulcerative Colitis Patients: Post Hoc Analysis of a Randomized Noninferiority Trial of 1600 mg vs 400 mg Tablets.

BACKGROUND The efficacy data on treatment in older adults are scarce, while the greatest increase in ulcerative colitis (UC) prevalence is observed in age groups of individuals 40 to 65 years of age and ≥65 years of age. AIM We assessed the difference in rates of clinical and endoscopic response and remission in UC adults (≤60 years) and older adults (>60 years) treated with mesalazine. METHODS We performed a post hoc analysis of data from a phase 3 noninferiority trial of 817 UC patients treated with mesalazine for 8 and additional 26 weeks in a double-blind and open-label study, respectively. We used Wilcoxon rank sum or chi-square test to analyze differences between groups and multivariable logistic regression to determine the associations between endoscopic remission as outcome (Mayo endoscopic subscore [MES] = 0 or ≤1) and independent variables including disease duration, baseline MES, age, sex, comedications, and comorbidities. RESULTS Older adults had a longer disease duration, a higher number of comorbidities, concomitant medications, and higher baseline MES (2.38 ± 0.486 in older adults vs 2.26 ± 0.439 in adults; P = .008) compared with adults. We observed no difference in rates of combined clinical and endoscopic remission, clinical remission and response, and endoscopic remission and response at week 8 and 38 post-treatment. In addition to other well-known predictors of worse outcome, patients with ≥3 comedications were less likely to achieve an MES = 0 at week 8 and 38 and an MES ≤1 at week 38. CONCLUSIONS We observed similar efficacy of mesalazine in adult and older adult UC patients. The increased comedication number rather than age may decrease effectiveness of UC medications, highlighting the importance of healthy aging.