Metformin use and risk of gastric adenocarcinoma in a Swedish population-based cohort study
Menée en Suède sur la période 2005-2015 auprès d'une cohorte de 544 130 personnes diabétiques et d'une cohorte témoin de 4 525 543 individus (durée médiane de suivi : 5,8 ans), cette étude analyse l'association entre une utilisation de la metformine et le risque d'adénocarcinome gastrique (7 287 cas)
Background : Whether or not the use of metformin decreases the risk of gastric adenocarcinoma is unclear. Methods : This was a population-based cohort study in 2005–2015. Associations between metformin use and gastric non-cardia and cardia adenocarcinomas were examined within two cohorts; a diabetes cohort of participants using anti-diabetes medications, and a matched cohort of common-medication users, where metformin non-users were frequency matched (10:1) with metformin users for sex and age. Multivariable Cox proportional hazard regression analyses provided hazard ratios (HR) and 95% confidence intervals (CI), adjusting for sex, age, calendar year, comorbidity, Helicobacter pylori eradication treatment, use of non-steroidal anti-inflammatory drugs or aspirin and use of statins. Results : During the follow-up for a median of 5.8 years, 892 (0.1%) participants in the diabetes cohort and 6395 (0.1%) participants in the matched cohort of common-medication users developed gastric adenocarcinoma. Metformin users had no significantly decreased risk of gastric non-cardia adenocarcinoma (diabetes cohort: HR 0.93, 95% CI 0.78–1.12; matched cohort: HR 1.30, 95% CI 1.18–1.42) or cardia adenocarcinoma (diabetes cohort: HR 1.49, 95% CI 1.09–2.02; matched cohort: HR 1.58, 95% CI 1.38–1.81) compared with non-users in both cohorts. Conclusions : This cohort study with <10 years of follow-up suggests metformin use may not prevent gastric adenocarcinoma.