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There have seen several studies evaluating the efficacy of anti-tumor necrosis factor (anti-TNF) compared with conventional therapy (i.e. immunomodulators, mesalamine, or placebo) at preventing postoperative Crohn's disease (CD) recurrence. The results of these studies have been variable and the magnitude by which anti-TNF therapy alters the natural history of CD in the postoperative setting has not yet been fully defined.", 'A comprehensive search of PubMed/MEDLINE, Scopus, CINAHL, and Cochrane databases was performed (May 2014). All studies on adult patients with CD that compared anti-TNF therapy versus conventional therapy or placebo to prevent CD recurrence were included. Meta-analysis was performed using the Mantel-Haenszel (fixed effects) model with odds ratio (OR) to assess for clinical remission.', 'In the pooled analysis, there was a higher frequency of achieving clinical remission beyond 1 year from time of surgery among patients receiving anti-TNF therapy compared with conventional therapy [OR 6.41; 95% confidence interval (CI) 2.88-14.27]. There was also a significantly higher rate of achieving both endoscopic (OR 26.44; 95% CI 10.48-66.68) and histologic remission (OR 9.80; 95% CI 2.54-37.81) in the anti-TNF therapy group compared with the conventional therapy group.
Is antitumor necrosis factor more effective than conventional medical therapy for the prevention of postoperative recurrence of Crohn 's disease : a meta-analysis?