Long-term prevention of post-operative recurrence in Crohn's disease cannot be affected by mesalazine.

Background: Prevention of post-operative recurrence has a central role in the management of Crohn's Disease (CD). Many drugs have been evaluated in prospective randomised controlled trials (RCTs) but the results are disappointing. Mesalazine, the drug more extensively investigated, has been shown to be effective for preventing recurrence in the short-term; however, the overall benefit is small and no data are available on the long-term effectiveness.

Aim: To compare the long-term occurrence of post-operative recurrence in patients who received regular prophylactic treatment with mesalazine with patients who did not receive prophylaxis after the first radical resection for ileo-caecal CD.

Patients And Methods: The records of 216 patients with ileo-caecal CD at their first resection were reviewed: 146 patients (67.6%) received post-operative prophylaxis with mesalazine while 70 patients (32.4%) received no prophylaxis. Allocation of patients in the two groups was determined by patients' preferences and by different policies in the post-operative prophylactic approach. The mean follow-up after surgery was 153.7 months (range 12-544). The co-primary endpoints were post-operative clinical and surgical recurrence.

Statistical Analysis: Kaplan-Meier survival method, Chi-square, Student t-test.

Results: The two groups were comparable with regard to gender, age at surgery, smoking habits, pattern of CD (perforating/not perforating), and disease duration before surgery. One year after surgery, a small, not statistically significant, risk reduction in clinical recurrence was observed in mesalazine treated group (-7.6%; 95% CI -18.0% to 2.8%). Within 10 years after surgery, the cumulative probability of clinical recurrence and surgical recurrence were similar in the two groups (Log Rank test p=0.9 and p=0.1 respectively).

Conclusion: Mesalazine prophylaxis is not effective for preventing the long-term post-operative recurrence in ileo-caecal Crohn's disease.