title: Assessing the effect of treatment duration on the association between anti-diabetic medication and cancer risk.
abstract: Most studies that have evaluated the association between anti-diabetic medication and cancer risk have suffered from methodological drawbacks. To avoid time-related biases, we evaluated the effect of treatment duration on the cancer risk among naive users of anti-diabetic medication as compared to non-users. In addition, we addressed the influence of common risk factors such as smoking and BMI. The study population comprised 23,394 participants of FINRISK surveys. Data on cancer and anti-diabetic medication were linked with the study cohorts. We applied Lexis tabulation to the data and analyzed split records by using Poisson regression. Changes in cancer incidence in relation to treatment duration were examined by modeling the rate ratio (RR). After a median follow-up of 9 years, 53 cancer cases among users of anti-diabetic medication and 1,028 among non-users were diagnosed. No significant difference in cancer risk between users and non-users was observed after adjustment. The RR for all medication regardless of its duration was 1.01 [95% CI 0.75-1.33], and 1.37 [0.94-1.94] for period of 1-4 years. The results were similar for metformin, sulfonylurea, and insulin. This study demonstrates that evaluation of the variation in cancer risk in relation to treatment duration is of particular importance for enhancing the accuracy of conclusions on the link between exposure to anti-diabetic medication and cancer risk.
authors.affiliation: Hjelt Institute, University of Helsinki, Helsinki, Finland.
authors.forename: Anna
authors.initials: A
authors.lastname: But
authors.affiliation: Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China.
authors.forename: Haining
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Satu
authors.initials: S
authors.lastname: Männistö
authors.affiliation: Finnish Cancer Registry, Helsinki, Finland.
authors.forename: Eero
authors.initials: E
authors.lastname: Pukkala
authors.affiliation: Hjelt Institute, University of Helsinki, Helsinki, Finland.
authors.forename: Jari
authors.initials: J
authors.lastname: Haukka
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006306:Health Surveys / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D012042:Registries / Q000706:statistics & numerical data; D018570:Risk Assessment / Q000379:methods* / Q000706:statistics & numerical data; D012307:Risk Factors; D012907:Smoking; D013997:Time Factors
chemical_list: D007004:Hypoglycemic Agents