Maintenance therapy with azathioprine (AZA)/6-mercaptopurine (6-MP) in Crohn's disease (CD) reduces the risk of re-operation particularly in smokers

Background/Aim:

Smoking has a key impact on the natural course of CD. Patients who smoke are more likely to develop clinical relapses, complications, operations and re-operations and to require immunosuppressant (IS). We aimed to asses the influence of smoking and IS on the risk of intestinal re-operation in CD.

Patients/Methods:

Medical charts of 563 patients have been analyzed retrospectively and patients were asked for smoking status after first surgery by standardized questionaires. From 254 cases with at least one resection, data for further analysis were available. Those patients were stratified into 4 groups: smokers with (n=61) and without IS (n=66) and nonsmokers (lifetime nonsmokers and quitters after first resection) with (n=54) and without IS (n=73). Chi-square test, stepwise logistic regression and Kaplan Meier analysis as statistic tests were performed.

Results:

Smoking habits after 1st surgery were represented by 127 smokers and 127 (50%) nonsmokers. Re-operation was performed in 112/254 (44%) patients, subsuming 63/127 (50%) smokers and 49/127(39%) nonsmokers (p=0.05). The probability to remain free of intestinal re-operation after 5 years was significantly reduced in smokers without IS vs. nonsmokers with IS (p=0.014), smokers with IS (p=0.011) and nonsmokers without IS (p=0.05). Multivariate analysis revealed no therapy with IS as a risk factor re-operation (OR 1.8; 95% CI 1.1–3.0) and a clear trend for smoking (OR 1.6; 95% CI 0.99–2.7).

Conclusion:

Our data suggest that maintenance therapy with IS in CD reduces the risk of reoperation particularly in smokers. Smokers should be advised to quit smoking and to start therapy with AZA/6-MP after first surgery.