Sulfasalazine and mesalazine for the maintenance therapy of Crohn's disease: a meta-analysis.

OBJECTIVE: The aim of this meta-analysis was to determine whether therapy with sulfasalazine or mesalazine is effective in the maintenance of clinical remission in patients with Crohn's disease. METHODS: Computerized searches of bibliographic databases were carried out to identify studies published up to October 1993 that were randomized controlled trials of sulfasalazine or mesalazine as single drug therapy in the prevention of symptomatic disease relapse in quiescent Crohn's disease. We extracted and statistically aggregated data from the trials, using a fixed effects model. RESULTS: A total of 10 eligible trials involving a total of 1022 patients were identified. Therapy with sulfasalazine or mesalazine reduces the risk of clinical relapse of Crohn's disease after 12 months [relative risk (RR) = 0.77, 95% confidence interval (CI) 0.64-0.92]. The benefit is less apparent at 3-6 months [RR = 0.86, 95% CI 0.67-1.09]. Subgroup analysis indicated that therapeutic benefit exists for mesalazine but not for sulfasalazine [RR for mesalazine = 0.63, 95% CI 0.50-0.79; RR for sulfasalazine = 1.08, 95% CI 0.81-1.44]. CONCLUSIONS: Maintenance therapy with mesalazine or sulfasalazine reduces the risk of clinical disease relapse in Crohn's disease after 1 yr. This benefit is seen primarily in the more recent studies that have used mesalazine as the therapeutic agent.