Twenty-one studies (n=3,655) were included in the review.
Ranitidine bismuth citrate-containing regimens (6 trials).
Seven different combination regimens and ten treatment arms were reported. The only combination with sufficient studies to combine using a meta-analysis was a triple therapy consisting of ranitidine bismuth citrate 400 mg, clarithromycin 500 mg and amoxicillin 1 g, all given twice daily for 7 days. There was no statistically significant difference in eradication rate between patients with PUD and those with NUD (summary RR 0.96, 95% CI: 0.84, 1.11). Heterogeneity was not statistically significant (P=0.56).
One study reported a statistically significant difference in H. pylori eradication between patients with PUD and those with NUD. The combination regimen consisted of ranitidine bismuth citrate 400 mg, clarithromycin 400 mg, amoxicillin 1 g and metronidazole 500 mg, all given twice daily for 5 days. The eradication rate was 100% in 174 patients with PUD and 87.3% in 71 patients with NUD (P<0.05).
PPI-based quadruple therapies (5 trials).
Four different combination regimens and six treatment arms were reported. A meta-analysis was not possible because of variability in the drug combinations. None of the studies reported a statistically significant difference in H. pylori eradication between patients with PUD and those with NUD.
Triple therapies comprising PPI, clarithromycin and amoxicillin (9 trials).
Nine different combination regimens and twelve treatment arms were reported. Six studies using a triple therapy consisting of a standard dose of a PPI, clarithromycin 500 mg and amoxicillin 1 g, all given twice daily for 7 days, were combined. The eradication rate in patients with PUD was statistically significantly higher than for patients with NUD (summary RR 1.15, 95% CI: 1.01, 1.29). However, there was statistically significant heterogeneity between studies (P=0.037). The summary risk difference was estimated at 0.11 (95% CI: -0.01, 0.22), giving an estimated NNT of 9. There was no evidence of statistically significant publication bias when using Egger's regression test (P=0.08).
A subgroup analysis was performed according to the type of publication. When the 4 studies that were published in abstract form were pooled, the difference in eradication rate was of borderline statistical significance in favour of PUD (summary RR 1.23, 95% CI: 1.00, 1.52). However, there was still statistically significant heterogeneity between studies (P=0.037).
Three studies using a triple therapy consisting of a standard dose of a PPI, clarithromycin 500 mg and amoxicillin 1 g, all given twice daily for 10 days, were combined. There was no statistically significant difference in eradication rate between patients with PUD and those with NUD (summary RR 1.03, 95% CI: 0.95, 1.12). Heterogeneity was not statistically significant (P=0.42).
Triple therapies comprising PPI, metronidazole and clarithromycin or amoxicillin (4 trials).
Five different combination regimens and five treatment arms were reported. A meta-analysis was not possible because of the variability in the drug combinations. None of the studies reported a statistically significant difference in H. pylori eradication between patients with PUD and those with NUD.