5-aminosalicylates prevent relapse of Crohn's disease after surgically induced remission: systematic review and meta-analysis.

OBJECTIVES: Evidence from randomized controlled trials (RCTs) for the use of 5-aminosalicylic acid (5-ASA) drugs in Crohn's disease (CD) in remission after a surgical resection is conflicting. We conducted a systematic review and meta-analysis of RCTs to examine this issue.
METHODS: MEDLINE, EMBASE, and the Cochrane central register of controlled trials were searched (through April 2010). Eligible trials recruited adults with luminal CD in remission after a surgical resection and compared 5-ASAs with placebo, or no treatment. Dichotomous data were pooled to obtain relative risk (RR) of relapse of disease activity, with a 95% confidence interval (CI). The number needed to treat (NNT) was calculated from the reciprocal of the risk difference.
RESULTS: The search strategy identified 3,061 citations. Eleven RCTs were eligible for inclusion containing 1,282 patients. The RR of relapse of CD in remission after surgery with 5-ASA vs. placebo or no therapy was 0.86 (95% CI=0.74-0.99) (NNT=13). Sulfasalazine was of no benefit in preventing relapse in 448 patients (RR=0.97; 95% CI=0.72-1.31), but mesalamine was more effective than placebo or no therapy (RR=0.80; 95% CI=0.70-0.92) in 834 patients, with an NNT of 10.
CONCLUSIONS: Mesalamine is of modest benefit in preventing relapse of CD in remission after surgery. Its use should be considered in those in whom immunosuppressive therapy is either not warranted or contraindicated.