ASPO Abstracts
Helicobacter pylori infections in Navajo communities of Northern Arizona
Category: Cancer Health Disparities
Conference Year: 2020
Abstract Body:
Purpose: Helicobacter pylori (Hp) is a gastric pathogen associated with development of duodenal or stomach ulcers, stomach cancer, and mucosa associated lymphoid-tissue (MALT) lymphomas. While Hp prevalence is declining in many regions, it varies by geographic location, ethnic background, socioeconomic status, and age. This project seeks to understand the role of Hp infection in development of stomach cancer among Native Americans of Northern Arizona, where stomach cancer incidence rates are approximately three times higher than the general population.
Methods: A cross-sectional survey was completed in summer 2018, based on a random sample of households selected using census block vectors for tribal lands overlaid onto satellite imagery. Potential household structures were marked and randomly sorted with recruitment goals set to be proportional to underlying population size. Structures were ground-truthed for eligibility and residents approached for participation. A total of 72 households were recruited with 105 self-identified Navajo >18 years from three communities in northern Arizona. Participants were assessed on household and individual level factors and a urea breath test (UBT) was performed to test for active infection. We used logistic regression, adjusted for household clustering, to calculate odds ratios (aOR) and 95% confidence intervals (CI) for associations between UBT results and individual and household factors.
Results: Active Hp infection was found in 66 of 101 participants with valid UBT, crude prevalence of 65.4%. Male participants were more likely to be positive (aOR=2.89, 95% CI, 1.03-8.09). Participants with an unregulated household water source had the highest odds for positive UBT (aOR=8.85, 95% CI, 1.50-53.38). There was no association with age or education.
Conclusions: Hp prevalence is high among individuals in these Navajo communities. Use of unregulated household water is strongly associated with active Hp infection. Further work is needed to determine potential geographic variation in prevalence and risk factors across tribal chapters and Hp virulence factors predominating in this population. Attention should focus to develop strategies to eradicate the infection among at-risk populations and target earlier detection.
Keywords: Helicobacter pylori, Native American, Prevalence, Stomach Cancer