Abstract: A total of 55 trials were included for one or more outcomes for this review. In duodenal ulcer healing, eradication therapy was superior to ulcer healing drug (UHD) (34 trials, 3910 participants, RR of ulcer persisting = 0.66, 95% confidence interval (CI) 0.58 to 0.76; 381/2286 (adjusted proportion: 12.4%) in eradication therapy plus UHD versus 304/1624 (18.7%) in UHD; low quality evidence) and no treatment (two trials, 207 participants, RR 0.37, 95% CI 0.26 to 0.53; 30/125 (adjusted proportion: 21.7%) in eradication therapy versus 48/82 (58.5%) in no treatment; low quality evidence). In gastric ulcer healing, the differences were imprecise between eradication therapy and UHD (15 trials, 1974 participants, RR 1.23, 95% CI 0.90 to 1.68; 220/1192 (adjusted proportion: 16.0%) in eradication therapy plus UHD versus 102/782 (13.0%) in UHD; very low quality evidence). In preventing duodenal ulcer recurrence the differences were imprecise between maintenance therapy with H.pylori eradication therapy and maintenance therapy with UHD (four trials, 319 participants, RR of ulcer recurring 0.73; 95% CI 0.42 to 1.25; 19/159 (adjusted proportion: 11.9%) in eradication therapy versus 26/160 (16.3%) in UHD; very low quality evidence), but eradication therapy was superior to no treatment (27 trials 2509 participants, RR 0.20, 95% CI 0.15 to 0.26; 215/1501 (adjusted proportion: 12.9%) in eradication therapy versus 649/1008 (64.4%) in no treatment; very low quality evidence). In preventing gastric ulcer recurrence, eradication therapy was superior to no treatment (12 trials, 1476 participants, RR 0.31, 95% CI 0.22 to 0.45; 116/697 (adjusted proportion: 16.3%) in eradication therapy versus 356/679 (52.4%) in no treatment; very low quality evidence). None of the trials reported proportion of people with gastric ulcer not healed after initial therapy between H.pylori eradication therapy and no active treatment or the proportion of people with recurrent gastric ulcer or peptic ulcers during maintenance therapy between H.pylori eradication therapy and ulcer healing drug therapy. Adding a one to two-week course of H. pylori eradication therapy is an effective treatment for people with H. pylori-positive duodenal ulcer when compared to ulcer healing drugs alone and no treatment. H. pylori eradication therapy is also effective in preventing recurrence of duodenal and gastric ulcer compared to no treatment. There is currently no evidence that H. pylori eradication therapy is an effective treatment in people with gastric ulcer or that it is effective in preventing recurrence of duodenal ulcer compared to ulcer healing drug. However, confidence intervals were wide and significant benefits or harms of H. pylori eradication therapy in acute ulcer healing of gastric ulcers compared to no treatment, and in preventing recurrence of duodenal ulcers compared to ulcer healing drugs cannot be ruled out.

Plain-language summary: Fifty-five studies provided information for the review. Thirty-four studies compared H. pylori eradication therapy plus ulcer-healing drug against ulcer-healing drug alone in the healing of duodenal ulcer. Two studies compared H. pylori eradication therapy against no treatment in the healing of duodenal ulcer. Fifteen studies compared H. pylori eradication therapy plus ulcer-healing drug against ulcer-healing drug alone in the healing of gastric ulcer. Three studies compared H. pylori eradication therapy plus ulcer-healing drug against ulcer-healing drug alone in the healing of peptic ulcer (gastric or duodenal ulcer). One study compared H. pylori eradication therapy against no treatment in the healing of peptic ulcer (gastric or duodenal ulcer). Four studies compared H. pylori eradication therapy against ulcer-healing drug in preventing the recurrence of duodenal ulcer after initial ulcer had been healed. Twenty-seven studies compared H. pylori eradication therapy against no treatment in preventing the recurrence of duodenal ulcer after initial ulcer had been healed. Twelve studies compared H. pylori eradication therapy against no treatment in preventing the recurrence of gastric ulcer after initial ulcer had been healed, while one study compared H. pylori eradication therapy against no treatment in preventing the recurrence of peptic ulcer (gastric or duodenal ulcer) after initial ulcer had been healed. Four studies compared H. pylori eradication therapy plus ulcer-healing drug versus comparison regimen in the relief of symptoms from peptic ulcer (gastric or duodenal ulcer). There were no studies comparing H. pylori eradication therapy against no treatment in the healing of gastric ulcer, H. pylori eradication therapy against ulcer-healing drug as maintenance therapy in preventing the recurrence of gastric ulcer after initial ulcer had been healed, or H. pylori eradication therapy plus ulcer-healing drug against no treatment or ulcer-healing drug in the relief of symptoms in people with peptic ulcer. Some trials provided information for more than one comparison. The evidence is current until March 2016. Adding a one to two-week course of H. pylori eradication therapy speeds up ulcer healing for people with H. pylori-positive duodenal ulcer when compared to ulcer-healing drugs alone and no treatment. H. pylori eradication therapy is also effective in preventing recurrence of duodenal and gastric ulcer (ulcer returning after initial healing) compared to no treatment. There is currently no evidence that H. pylori eradication therapy is an effective treatment in people with gastric ulcer or that it is effective in preventing recurrence of duodenal ulcer compared to ulcer-healing drugs. However, because of the small number of studies included for the last two comparisons, significant benefits or harms of H. pylori eradication therapy in acute ulcer healing of gastric ulcers compared to no treatment and in preventing recurrence of duodenal ulcers compared to ulcer healing drugs cannot be ruled out. The quality of evidence was low or very low because most of the studies had errors in study design. As a result, there is a lot of uncertainty regarding the results.