Age at Acquisition of Helicobacter pylori Infection: Comparison of Two Areas with Contrasting Risk of Gastric Cancer

Abstract

The prevalence of infection was similarly high and increased with age in both populations. In these populations the age of acquisition of H. pylori after 1 year of age does not appear to be a primary factor responsible for the differences in the rates of gastric cancer incidence in adults. Previous findings in adults showed lower prevalence of the most virulent genotypes in Tumaco compared to Pasto, and bacterial virulence may play a key role in determining cancer outcome.

Intestinal Helminthiasis in Colombian Children Promotes a Th2 Response to Helicobacter pylori: Possible Implications for Gastric Carcinogenesis

“…Once infected, environmental influences, such as antioxidant levels in diet, have been suggested to affect progression of disease (14). Additional risk factors affecting the outcome of H. pylori infection include unexplained geographic differences in the incidence of gastric cancer even after controlling for factors, such as age at first exposure to H. pylori (15) and immunologic differences in the response to the chronic infection (16).…”

Gastric Cancer is Related to Early Helicobacter pylori Infection in a High-Prevalence Country

“…The inconsistencies that have been described in the association between H. pylori and gastric cancer at the population level (27,28) may be explained in part by the lack of accuracy in serologic testing and by variations in study conditions. We did not find a spatial association between gastric cancer and H. pylori when analyzed at the level of large conglomerates-the 13 regions of the country-the association was only evident in smaller geographic units, that is, the 333 counties.…”

“…The use of large populations may explain the lack of association between H. pylori and mortality from gastric cancer in Mexico (27). A recent study in Colombia (28) reports an equal infection rate of H. pylori in areas of high (Pasto) and low (Tumaco) risk for gastric cancer (59.7% and 58.6%, respectively). This apparent paradox could be explained by racial differences (as stated by the authors, Pasto is predominantly Spanish-Amerindian, whereas Tumaco is predominantly of African-Spanish ancestry) or the environmental differences between the two cities (Pasto is at a high altitude in the Andean mountains and is mostly agricultural, whereas Tumaco is by the Pacific coast).…”

La otra transición epidemiológica: hitos en el desarrollo de la epidemiología de los factores de riesgo en Colombia

“…Los estudios posteriores exploraron la relación entre Helicobacter pylori y el cáncer gástrico (54), y encontraron relaciones fuertes con algunos genotipos bacterianos (55). Por esta razón, algunos estudios se encaminaron a estudiar los factores que predisponen a la adquisición de la infección, y encontraron constantemente su aparición temprana en la niñez entre poblaciones con gran frecuencia de cáncer (56). Una línea de investigación actual es la prevención de su presentación mediante el uso de antioxidantes, como la vitamina C (57).…”