Abstract B45: Seroprevalence of H. pylori in Puerto Rico
Authors: Gonzalez-Pons Maria del Mar , Soto-Salgado Marievelisse , Sevilla Javier , Suarez Erick L. , Perez Cynthia M. , Marquez-Lespier Juan M. , Cruz-Correa Marcia 
Published: May 2016

Background: Gastric cancer (GC) is the 4th most common incident cancer and the 2nd leading cause of cancer death worldwide. Approximately 990,000 people are diagnosed with GC worldwide, of whom close to 75% die from this disease. Despite the overall decrease in the global incidence of GC since the 1930s, GC disease is one of the top ten most diagnosed cancers and leading cause of cancer death in Puerto Rico. Risk factors for the development of gastric cancer include: male sex, older age, Helicobacter pylori status, tobacco smoking, diet, living in places with high altitude, low socioeconomic status, and being part of the Asian, Hispanic, and African American communities. However, the prevalence of H. pylori, one of the main risk factors for GC, is unknown in the Puerto Rican Hispanic population. Prevalence of H. pylori infection is influenced by socioeconomic, demographic, and ethnic factors. Thus, this study aimed to determine the seroprevalence and associated risk factors for H. pylori infection among a sub-sample of Puerto Rican Hispanics.

Methods: A cross sectional study was designed using an existing population-based biobank that comprised of 1,645 serum samples collected in the parent study “Epidemiology of hepatitis C in the household population of Puerto Rico”. The Premier™ H. pylori enzyme immunoassay (Meridian Bioscience, Inc.) was used to determine the seroprevalence according to the manufacturer's specifications. A prevalence estimate of H. pylori was estimated using logistic regression models according to sociodemographic characteristics. Differences between groups according to H. pylori status were assessed using Student's t-test or Mann-Whitney test for continuous variables, and χ² test or Fisher's exact test, when appropriate, for categorical variables. Multivariable logistic regression models were fitted to estimate the prevalence ratio (PR) with 95% CIs for H. pylori seropositivity. All data was analyzed using Stata for Windows release 13.0 (Stata Corporation, College Station, Texas, USA).

Results: A total of 528 representative serum samples (by age, gender, population density, and years of education) from the 1654 were analyzed. The majority of participants were females (55.3%), aged 30-49 years (50.2%), born in PR (89.6%), had ≥ 12 years of education (76.3%), had an annual family income &lt; $20,000 (64.1%), and had health insurance (88.8%). The overall seroprevalence of H. pylori was 35.2% (95% CI=31.2-39.5; females 54.8%). Statistically significant differences in terms of age, place of birth, marital status, years of education, annual family income, type of health insurance, place of residence, and population density were observed when comparing individuals with seropositive to H. pylori and individuals without (p&lt;0.05). Seroprevalence of H. pylori increased according to age-strata; where those ages 30-49 had prevalence of 1.49 (95% CI 1.01-2.18), while those ages 50-64 had higher prevalence of 2.28 (95% CI 1.57-3.33). Individuals born in Puerto Rico had higher seropositive prevalence of H. pylori, compared to individuals not born on the island (PR=2.29; 95% CI=1.24-4.20). The prevalence of H. pylori among individuals living in high-density population areas was higher than those living in low-density areas (PR=0.71, 95% CI=0.56-0.90, p-value=0.005).

Conclusions: This is the first report of the seroprevalence of H. pylori in the Puerto Rican Hispanic population. The observed prevalence of H. pylori in Puerto Rican Hispanics is lower than rates reported for US Hispanics and similar to US non-Hispanics. The lower prevalence of H. pylori among individuals living in high-density population areas may be a surrogate for wealth and/or environmental exposures. In summary, the observed health disparities among the Puerto Rican population with regards to H. pylori seroprevalence may impact the incidence of gastric neoplasia and warrant further investigation.

Citation Format: Maria del Mar Gonzalez-Pons, Marievelisse Soto-Salgado, Javier Sevilla, Erick L. Suarez, Cynthia M. Perez, Juan M. Marquez-Lespier, Marcia Cruz-Correa. Seroprevalence of H. pylori in Puerto Rico. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B45.