Aim of study: To evaluate the efficacy of 5-aminosalicylic acid (5-ASA) in preventing recurrences of Crohn's disease.
Patients and methods: Between January 1988 and December 1989 a total of 60 patients (37 men, 23 women, mean age 34.8 years) were selected in whom the diagnosis of Crohn's disease had been known for at least 2 years. A further criterion for inclusion was remission for at least one year in patients who had been operated or for one month in the nonoperated ones. Furthermore, the latter must have had at least one recurrence during the last year. They were in turn assigned to be treated with 5-ASA (2.4 g daily by mouth) or not treated (control). The activity and localization of Crohn's disease were defined according to the "Crohn's disease activity index" (CDAI) and the "laboratory index" (LI), as well as by endoscopy and (or) radiology. The patients were examined every 6 months for 4 years. A recurrence was diagnosed if the CDAI was more than 150 or had increased to at least 60 points above the initial value and the LI was above 100.
Results: 29 recurrences were noted, 72.4% within the first 2 years. 15 recurrences (46.9%) were in the treated patients and 14 (58.3%) among the untreated controls. The Kaplan-Meier curve (statistical comparison of the probability of recurrence) showed no significant difference between the two groups (P = 0.23): the recurrence rate was the same in the two groups, among the patients with or without previous operation and for different primary localizations. There were no notable side effects.
Conclusion: Treatment with 5-ASA was not found to influence the likelihood of recurrence. Age, duration of the disease, primary localization and previous operation were not prognostic factors.