Poster presentation: Meta-analysis of misoprostol in the prevention of gastroduodenal (GD) ulcers in patients taking nonsteroidal anti-inflammatory drugs (NSAIDs)

Ferraz M. B., Maetzel A. and Bombardier C. McMaster University, Dept. CE&B - 2C7, 1200 Main Street West, Hamilton, Ontario L8N 3Z5, Canada.

Introduction/Objective: Endoscopically proven gastric ulcers are present in 12% to 28% of patients taking regular NSAIDs. Misoprostol, a synthetic prostaglandin El analogue, has been shown to reduce the frequency of GD ulcers in patients taking NSAIDs. This study evaluates the effectiveness of misoprostol according to various ulcer definitions in "evaluable" (E) and "intent-to-treat" (ITT) patient cohorts.
Methods: A Medline search was performed to identify all randomized controlled endoscopic studies published in scientific journals from 1985 to December 1994, evaluating the effectiveness of misoprostol 800 Ug/day in preventing GD ulcers in patients on NSAIDs. All manuscripts and their bibliographies were reviewed and were only considered eligible for inclusion in this overview if they were double-blind, had longer than 1 month' follow-up, presented an endoscopy at baseline and end of the trial, and reported enough data about the frequency of GD ulcers. Effectiveness in terms of preventing GD ulcers was defined as relative risk reduction (RRR). The number-needed-to-treat (NNT) to prevent an ulcer was also calculated.
Results: Four studies were eligible for inclusion in this meta-analysis. The overall number of patients randomized to the Misoprostal+NSAID and Placebo+NSAID groups were nM=698 and nP=5l4, respectively. The following overall RRR (95% CI) were observed according to the ulcer definition and patient cohort considered, ITT or E:

Ulcer definition nM nP ITT nM nP E

G+D ulcers > O.5 cm 380 376 0.82 (0.67-0.95) 45 25 1.00 (-----)

G+D ulcers < 0.5 cm 60 53 0.90 (0.79-1.00) --- --- -----

G ulcers > 0.3 cm 140 138 0.90 (0.77-1.00) 261 138 0.93 (0.85-1.00)

G ulcers > 0.5 cm 259 138 0.91 (0.76-1.00) --- --- -----

D ulcers > 0.5 cm 380 376 0.89 (0.64-1.00) 213 232 0.85 (0.53-1.00)

Three to 27 patients would need to be treated with Misoprostol to prevent a GD ulcer.
Discussion: Misoprostol is an effective treatment to prevent various GD ulcer sizes in patients on NSAIDs. The results are robust whether an ITT or E Cohort analysis is used.

Oslo 1995 P42