Prevalence of mucosal lesions in the stomach and duodenum due to chronic use of NSAID in patients with rheumatoid arthritis or osteoarthritis, and interim report on prevention by misoprostol of diclofenac associated lesions.

We review preliminary findings of the screening and prophylaxis phases of a study of misoprostol in patients with arthritis receiving nonsteroidal antiinflammatory drugs (NSAID). Endoscopic evaluation of over 1,800 patients with rheumatoid arthritis or osteoarthritis, more than 95% of whom qualified for screening on the basis of continuous NSAID use over the prior 6 months, has revealed clinically significant gastroduodenal lesions in 37% and ulceration in 24%. In the prophylaxis phase, patients without significant lesions were randomized to receive misoprostol or placebo and NSAID therapy with diclofenac for 52 weeks. Product-limit and crude incidence analyses of data from patients thus far enrolled indicate that misoprostol is associated with significant protection against the development of gastroduodenal lesions compared with placebo after 12 or 24 weeks of study. No adverse effect of misoprostol administration on underlying arthritis activity has been observed thus far. Definitive conclusions await completion of the study.