Clinical and economic effects of population-based Helicobacter pylori screening to prevent gastric cancer

Background: Helicobacter pylori infection has been identified as a risk fac tor for certain types of gastric cancer. However, the extent to which H pyl ori eradication decreases the risk of gastric cancer is unknown, raising th e question of whether population-based H pylori screening should be underta ken. Objective: To compare clinical and economic effects of H pylori screening, with and without confirmatory testing, with no screening to prevent gastric cancer. Design: Decision analysis incorporating a Markov simulation. Patients: Simulated cohorts of men and women with varying risk of gastric c ancer. Intervention: Three strategies were evaluated. (1) no screening; (2) H pylo ri serologic testing, treat those positive for H pylori no follow-up testin g; and (3) H pylori serologic testing, treat those positive for H pylori, f ollowed by a test to confirm H pylori eradication, retreat those who test p ositive. In the principal analysis, the risk of gastric cancer after H pylo ri eradication was assumed to be similar to that for those without H pylori infection. Scenarios with less optimistic assumptions regarding risk reduc tion of cancer were evaluated. Main Outcome Measures: Gastric cancer rates, discounted cost per life-year saved. Results: If H pylori eradication reduced the risk of cancer to that of peop le never infected, both H pylori intervention strategies reduced gastric ca ncer rates so that each yielded at least 12 additional life-years per 1000 40-year old white men screened when compared with no screening. Helicobacte r pylori serologic testing without posttreatment confirmatory testing resul ted in the lowest cost per additional life-year saved ($6264). The cost-eff ectiveness of the H pylori screening strategies varied substantially as the level of risk reduction of cancer was varied, but remained cost-effective even at moderate rates (<30%) of excess risk reduction of cancer in all coh orts evaluated. Conclusions: Population-based H pylori screening has the potential to produ ce important health benefits at a reasonable cost at moderate rates of exce ss risk reduction of cancer. Controlled studies are necessary to confirm an d quantify the impact of H pylori eradication on the risk of gastric cancer .