A large randomised controlled intervention trial to prevent gastric cancer by eradication of Helicobacter pylori in Linqu County, China: baseline results and factors affecting the eradication.

OBJECTIVE: To clarify the full range of benefits and adverse consequences of Helicobacter pylori eradication as a strategy for gastric cancer prevention, the community-based intervention trial was launched in Linqu County, China. DESIGN: A total of 184,786 residents aged 25-54 years were enrolled in this trial and received (13)C-urea breath test. H. pylori positive participants were assigned into two groups, either receiving a 10-day quadruple anti-H. pylori treatment or lookalike placebos together with a single dosage of omeprazole and bismuth. RESULTS: The prevalence of H. pylori in trial participants was 57.6%. A total of 94,101 subjects completed the treatment. The overall H. pylori eradication rate was 72.9% in the active group. Gender, body mass index, history of stomach disease, baseline delta over baseline-value of (13)C-urea breath test, missed medication doses, smoking and drinking were independent predictors of eradication failure. The missed doses and high baseline delta over baseline-value were important contributors in men and women (all Ptrend<0.001). However, a dose-response relationship between failure rate and smoking or drinking index was found in men (all Ptrend<0.001), while high body mass index (Ptrend<0.001) and history of stomach disease were significant predictors in women. The treatment failure rate increased up to 48.8% (OR 2.87, 95% CI 2.24 to 3.68) in men and 39.4% (OR 2.67, 95% CI 1.61 to 4.42) in women with multiple factors combined. CONCLUSIONS: This large community-based intervention trial to eradicate H. pylori is feasible and acceptable. The findings of this trial lead to a distinct evaluation of factors influencing eradication that should be generally considered for future eradication therapies. TRIAL REGISTRATION NUMBER: ChiCTR-TRC-10000979 in accordance with WHO ICTRP requirements.

Gastric cancer prevention by community eradication of Helicobacter pylori: a cluster-randomized controlled trial.

Gastric cancer is a leading cause of cancer-related deaths in China. Affecting more than 40% of the world's population, Helicobacter pylori is a major risk factor for gastric cancer. While previous clinical trials indicated that eradication of H. pylori could reduce gastric cancer risk, this remains to be shown using a population-based approach. We conducted a community-based, cluster-randomized, controlled, superiority intervention trial in Linqu County, China, with individuals who tested positive for H. pylori using a 13C-urea breath test randomly assigned to receiving either (1) a 10-day, quadruple anti-H. pylori treatment (comprising 20 mg of omeprazole, 750 mg of tetracycline, 400 mg of metronidazole and 300 mg of bismuth citrate) or (2) symptom alleviation treatment with a single daily dosage of omeprazole and bismuth citrate. H. pylori-negative individuals did not receive any treatment. We examined the incidence of gastric cancer as the primary outcome. A total of 180,284 eligible participants from 980 villages were enrolled over 11.8 years of follow-up, and a total of 1,035 cases of incident gastric cancer were documented. Individuals receiving anti-H. pylori therapy showed a modest reduction in gastric cancer incidence in intention-to-treat analyses (hazard ratio 0.86, 95% confidence interval 0.74-0.99), with a stronger effect observed for those having successful H. pylori eradication (hazard ratio 0.81, 95% confidence interval 0.69-0.96) than for those who failed treatment. Moderate adverse effects were reported in 1,345 participants during the 10-day treatment. We observed no severe intolerable adverse events during either treatment or follow-up. The findings suggest the potential for H. pylori mass screening and eradication as a public health policy for gastric cancer prevention. Chinese Clinical Trial Registry identifier: ChiCTR-TRC-10000979 .