Methods: We developed a state-transition model that simulates the natural history of intestinal type GC in China and calibrated it to age-specific prevalence of precancerous lesions and cancer. For a cohort of 30-year old males, we estimated life expectancy (LE) and lifetime costs (2003 US$) for the following strategies: 1) no screening, 2) Hp screening and treatment, and 3) universal Hp treatment. Based on clinical trial data we assumed treatment was only effective in individuals who had not yet developed precancerous lesions. Assumptions related to Hp prevalence, screening performance, treatment efficacy and costs were explored using sensitivity analysis.
Results: In the absence of Hp screening or treatment, discounted per-person lifetime costs were $37 and LE was 23.36 years. Hp screening reduced lifetime intestinal type GC incidence by 6% and had an incremental cost-effectiveness ratio (ICER) of $2,020/LYS, compared to no screening. In comparison, universal Hp treatment increased costs by $6 per person and had an ICER of $6,900/LYS. Given a cost-effectiveness threshold equivalent to 3-times the GDP per capita ($2,940), screening and treatment is reasonable value for money. Results were most sensitive to treatment efficacy and costs; for example, as the cost of antibiotics was reduced from $23 to $12, the ICER for screening was reduced to <1-times the GDP per capita. Universal treatment was the preferred strategy only if Hp prevalence levels were >90% or if treatment reduced the risk of precancerous lesions by >85%.
Conclusions: Clinical trials investigating the effectiveness of Hp treatment are underway but information on the long-term impact of treatment on cancer reduction may not be available for several years. Using the data available now, and relying on modeling techniques to extrapolate from studies reporting intermediate outcomes, Hp screening has the potential to be cost-effective, and with reduced treatment costs could be very cost-effective with ICERs that are as attractive as other well-accepted public health interventions.