title: Metformin and the risk of endometrial cancer: a case-control analysis.
abstract: OBJECTIVE
  To explore the risk of endometrial cancer in relation to metformin and other antidiabetic drugs.
  
  
  METHODS
  We conducted a case-control analysis to explore the association between use of metformin and other antidiabetic drugs and the risk of endometrial cancer using the UK-based General Practice Research Database (GPRD). Cases were women with an incident diagnosis of endometrial cancer, and up to 6 controls per case were matched in age, sex, calendar time, general practice, and number of years of active history in the GPRD prior to the index date. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated and results were adjusted by multivariate logistic regression analyses for BMI, smoking, a recorded diagnosis of diabetes mellitus, and diabetes duration.
  
  
  RESULTS
  A total of 2554 cases with incident endometrial cancer and 15,324 matched controls were identified. Ever use of metformin compared to never use of metformin was not associated with an altered risk of endometrial cancer (adj. OR 0.86, 95% CI 0.63-1.18). Stratified by exposure duration, neither long-term (≥25 prescriptions) use of metformin (adj. OR 0.79, 95% CI 0.54-1.17), nor long-term use of sulfonylureas (adj. OR 0.96, 95% CI 0.65-1.44), thiazolidinediones (≥15 prescriptions; adj. OR 1.22, 95% CI 0.67-2.21), or insulin (adj. OR 1.05 (0.79-1.82) was associated with the risk of endometrial cancer.
  
  
  CONCLUSIONS
  Use of metformin and other antidiabetic drugs were not associated with an altered risk of endometrial cancer.
authors.affiliation: Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Switzerland.
authors.forename: Claudia
authors.initials: C
authors.lastname: Becker
authors.forename: Susan S
authors.initials: SS
authors.lastname: Jick
authors.forename: Christoph R
authors.initials: CR
authors.lastname: Meier
authors.forename: Michael
authors.initials: M
authors.lastname: Bodmer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D016889:Endometrial Neoplasms / Q000139:chemically induced / Q000453:epidemiology*; D005260:Female; D058006:General Practice / Q000706:statistics & numerical data; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D015994:Incidence; D016015:Logistic Models; D008687:Metformin / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D007004:Hypoglycemic Agents; D008687:Metformin