Smoking as a risk factor for duodenal ulcer relapse. RUDER Study Group.

This study reports the influence of smoking on the two-year relapse rate of duodenal ulcers under treatment with ranitidine. 1899 patients with a healed duodenal ulcer received 150 mg ranitidine daily for one year, 1671 patients for two years. During this time period 23.4% of smokers relapsed compared with 26.3% of ex-smokers and 18.0% of non-smokers. The difference between smokers and ex-smokers versus non-smokers was statistically significant. There were significantly fewer relapses among smokers who stopped smoking (14.2%) compared with smokers who continued to smoke (25.2%) during maintenance treatment. These results show that continued and past smoking significantly increase the two-year relapse rate of duodenal ulcers during maintenance treatment with ranitidine.