The efficacy and safety of non‐steroidal anti‐inflammatory drugs in preventing the recurrence of colorectal adenoma: a meta‐analysis and systematic review of randomized trials

AIM: We report a meta-analysis and systematic review of randomized trials assessing the impact of non-steroidal anti-inflammatory drugs (NSAIDs) in preventing recurrence of colorectal adenoma. METHOD: PubMed/Medicine, EMBASE and the Cochrane Central Register of Controlled Trials databases were searched for relevant randomized double-blind placebo-controlled trials published before March 2014. Two authors independently assessed study quality and extracted data. stata software was used to investigate heterogeneity between studies, and analysis was performed using a fixed-effects model to calculate and merge data. RESULTS: Nine studies, with 8521 subjects, were included. Results were categorized by the duration of follow-up. The relative risks of any recurrence of adenoma in patients receiving NSAIDs compared with the placebo group were 0.68 [95% confidence interval (CI) 0.63-0.73, P = 0.001] for patients with a 1-year follow-up, 0.75 (95% CI 0.68-0.83, P = 0.246) with 3 years and 1.43 (95% CI 1.14-1.79, P = 0.127) with follow-up of over 3 years. Using pooled risk ratios, NSAIDs were associated with a significant decrease in adenoma recurrence at 1 and 3 years, although this association was lost beyond 3 years of follow-up. For secondary prevention of advanced adenomas, the pooled risk ratios (compared with placebo) were 0.51 (95% CI 0.43-0.60, P = 0.026) after 1 year, 0.61 (95% CI 0.50-0.76, P = 0.887) at 3 years and 1.39 (95% CI 0.89-2.16, P = 0.829) after 3 years. CONCLUSION: The meta-analysis indicated that oral NSAIDs may be effective in the early prevention of secondary occurrence of adenomas.