Risk and protective factors for gastric metaplasia and cancer: a hospital-based case-control study in Ecuador

Introduction: worldwide, stomach cancer is the fifth most frequent cancer, with 952 000 new cases diagnosed in 2012. Ecuador currently holds the 15th place of countries with the highest incidence of stomach cancer for both sexes. Objectives: the objective of this study was to evaluate risk and protective factors for gastric cancer/metaplasia. Methods: a hospital-based case-control study was conducted in Quito, Ecuador. Cases were defined as patients with histological confirmation of gastric cancer (N=60) or incomplete gastric metaplasia (N=53). Controls were defined as patients free of gastric cancer or premalignant lesions (N=144). All participants were personally interviewed using a structured questionnaire to collect data about dietary habits, lifestyle and medical history. Results: risk factors significantly associated to the presence of gastric cancer/metaplasia were the consumption of reheated foods at least 3 times per week (AOR: 4.57; CI: 2.2-9.5) and adding salt to more than 50% of foods (AOR: 1.32; CI: 1.04-1.67). Protective factors for gastric cancer/metaplasia were the use of non-steroidal anti-inflammatory drugs (AOR: 0.39; CI 0.19-0.83), age less than 58 years old (AOR: 0.38; CI: 0.18-0.79) and have received treatment for H. Pylori infection (AOR: 0.33; CI: 0.16-0.71). Conclusions: this study reports for the first time, the risk and protective factors associated with gastric cancer and metaplasia in Ecuador.