Objectives: Maintenance therapy with 5-aminosalicylates (5-ASAs) is recommended in patients with quiescent ulcerative colitis (UC), but compliance rates are low. Once-daily dosing may improve adherence, but impact on the relapse of disease activity is unclear as no previous meta-analysis has studied this issue.
Methods: MEDLINE, EMBASE, and the Cochrane central register of controlled trials were searched (through April 2011). Eligible randomized controlled trials (RCTs) recruited adults with quiescent UC, and compared once-daily dosing of 5-ASAs with a more frequent dosing schedule of an identical total daily dose of the same 5-ASA drug. Minimum treatment duration was 6 months. Trials reported a dichotomous assessment of relapse of disease activity at last point of follow-up. Data concerning non-compliance and adverse events were extracted, where reported. Effect of once-daily vs. more frequent dosing schedule was reported as relative risk (RR) of relapse with a 95% confidence interval (CI).
Results: The search identified 3,061 citations, and seven RCTs containing 2,745 patients were eligible. All RCTs used mesalamine. Relapse rates were not significantly different between once-daily and conventional dosing schedules for mesalamine (RR of relapse=0.94; 95% CI: 0.82-1.08). Non-compliance (RR=0.87; 95% CI: 0.46-1.66) and adverse events were no more likely with once-daily dosing (RR=1.08; 95% CI: 0.97-1.20).
Conclusions: Once-daily dosing with mesalamine is as effective as conventional dosing schedules for the prevention of relapse of quiescent UC, although there is no definitive evidence that compliance with once-daily dosing is better. Adverse events occur at a similar frequency.