Helicobacter Pylori and the Birth Cohort Effect: Evidence for Stabilized Colonization Rates in Childhood

Abstract

Background The prevalence of Helicobacter pylori has declined over recent decades in developed countries. The increasing prevalence with age is largely due to a birth-cohort effect. We previously observed a decline in H. pylori prevalence in 6- to 8-year old Dutch children from 19% in 1978 to 9% in 1993. Knowledge about birth-cohort-related H. pylori prevalence is relevant as a predictor for the future incidence of H. pylori-associated conditions. Aim The aim of this study was to investigate whether the birth-cohort effect of H. pylori observed between 1978 and 1993 continued in subsequent years. Methods Anti-H. pylori IgG antibodies and anti-CagA IgG antibodies were determined in serum samples obtained in 2005/2006 from 545 Dutch children aged 7–9 years who participated in the PIAMA birth cohort. The H. pylori and CagA antibodies were determined by ELISAs that have been extensively validated in children, with a 94% sensitivity for Hp colonization and a 92.5% sensitivity for colonization with a cagA-positive strain. Results Of the 545 children (M/F 300/245), most (91.5%) were of Dutch descent. The H. pylori positivity rate was 9% (95% CI 6.6–11.4%). The prevalence of CagA antibodies was 0.9% (95% CI 0.1–1.6%). No significant differences were demonstrated in H. pylori and cagA prevalence in relation to gender or ethnicity. Conclusion The prevalence of H. pylori in childhood has remained stable in the Netherlands from 1993 to 2005, suggesting a stabilization of the previously decreasing trend in subsequent birth cohorts. This finding may reflect stabilization in determinants such as family size, housing, and hygienic conditions (or offset by day care). If confirmed in other populations in developed countries, it implies that colonization with H. pylori will remain common in the coming decades. Remarkably however, the rate of colonization with cagA+ H. pylori strains has become very low, consistent with prior observations that cagA+ strains are disappearing in Western countries.

Helicobacter pyloriinfection is associated with advanced colorectal neoplasia

“…In previous studies, insufficient numbers of subjects with colorectal neoplasia were enrolled compared to our study. We included patients with a history of colorectal neoplasia found on previous colonoscopies, since H. pylori infection is acquired during childhood and adolescence [7] with almost no new infections in adulthood [20], thus increasing the number of diagnosed colorectal neoplasia after age adjustment. Deciding on the patients' outcome status only from the last current colonoscopy without referring to previous colonoscopic results, which may contain information about polyps or cancer lesions that have been removed in the past, could cause misclassification into the negative group (no findings) of patients that actually have had neoplastic lesions in their past.…”

“…If the second examination was also incomplete, the results were excluded from the analysis. Since H. pylori infection is acquired mostly during childhood and adolescence [7] with almost no new infections in adulthood [20], we searched the participants' medical files for previous colonoscopies and included positive findings of neoplastic lesions instead of the present negative findings, since colonoscopy after a previous polypectomy can be negative. Thus, using only present colonoscopy findings without taking into account previous findings, can lead to underestimation of the association.…”

Changing prevalence ofHelicobacter pyloriinfection in the 9th district of Budapest. A retrospective endoscopic study, 1997–2012

“…Ennek ellentmond, hogy egy holland tanulmányban a H. pylori kolonizációja gyermekekben 1978 és 1992 között csökkent, de 1993-2005-ben stabil, 9% (95% KT: 6,6-11,4%) értéken maradt. Ezt a szerzők a szociális ténye-zők és higiénés feltételek változatlan színvonalával magyarázták [18].…”

Lifestyle and Gastric Function

“…Some recent data suggest that this phenomenon may have slowed down or come to a halt, which is likely related to stabilization of environmental exposure. A further Dutch study using the same methods found that the prevalence of H. pylori had stabilized at 9% in children aged 7-9 years between 1993 and 2006 [5]. The cause of this apparent stabilization remains unclear.…”