Trends in Helicobacter pylori infection among Māori, Pacific, and European Birth cohorts in New Zealand.

Background: The aim of this paper is to estimate the seroprevalence of Helicobacter pylori infection in the New Zealand population by ethnicity and year of birth.

Methods: A systematic search identified seven studies in New Zealand that reported prevalence of H. pylori infection among 4463 participants. Prevalence data were pooled to estimate the Māori, Pacific, and European seroprevalence of H. pylori in four birth cohorts (1926-40, 1941-55, 1956-70, and 1971-85), by assuming that infection is acquired in childhood and seroprevalence is stable with aging. The best estimates of national seroprevalence were obtained by geographic regional weighting and corrections for selection and measurement bias.

Results: Infection rates among all ethnic groups declined in more recent birth cohorts. Prevalence was highest among Pacific peoples (ranging from 39-83%) followed by Māori (18-57%) and then European (7-35%). The absolute ethnic differences in seroprevalence decreased in subsequent cohorts, but the relative ethnic differences increased.

Conclusions: There is scope to much further reduce Māori and especially Pacific people's risk of H. pylori infection. Solutions to reduce H. pylori prevalence and its sequelae should focus on people at greatest risk of the infection. Further evaluation of strategies to address H. pylori infection is warranted. Interventions to be evaluated could include household crowding reduction and eradication therapy for asymptomatic infected persons to reduce their risk of noncardia stomach cancer.