TY - JOUR
T1 - Metformin does not affect cancer risk
T2 - A cohort study in the U.K. clinical practice research datalink analyzed like an intention-to-treat trial
AU - Tsilidis, Konstantinos K.
AU - Capothanassi, Despoina
AU - Allen, Naomi E.
AU - Rizos, Evangelos C.
AU - Lopez, David S.
AU - Van Veldhoven, Karin
AU - Sacerdote, Carlotta
AU - Ashby, Deborah
AU - Vineis, Paolo
AU - Tzoulaki, Ioanna
AU - Ioannidis, John P.A.
PY - 2014/9
Y1 - 2014/9
N2 - OBJECTIVE: Meta-analyses of epidemiologic studies have suggested that metformin may reduce cancer incidence, but randomized controlled trials did not support this hypothesis. RESEARCH DESIGN AND METHODS A retrospective cohort study, Clinical Practice Research Datalink, was designed to investigate the association between use of metformin compared with other antidiabetes medications and cancer risk by emulating an intention-to-treat analysis as in a trial. A total of 95,820 participants with type 2 diabetes who started taking metformin and other oral antidiabetes medications within 12 months of their diagnosis (initiators) were followed up for first incident cancer diagnosis without regard to any subsequent changes in pharmacotherapy. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HR) and 95% CI. RESULTS: A total of 51,484 individuals (54%) were metformin initiators and 18,264 (19%) were sulfonylurea initiators, and 3,805 first incident cancers were diagnosed during a median follow-up time of 5.1 years. Compared with initiators of sulfonylurea, initiators of metformin had a similar incidence of total cancer (HR 0.96; 95% CI 0.89-1.04) and colorectal (HR 0.92; 95% CI 0.76-1.13), prostate (HR 1.02; 95% CI 0.83-1.25), lung (HR 0.85; 95% CI 0.68-1.07), or postmenopausal breast (HR 1.03; 95% CI 0.82-1.31) cancer or any other cancer. CONCLUSIONS: In this large study, individualswith diabetes who usedmetformin had a similar risk of developing cancer compared with those who used sulfonylureas.
AB - OBJECTIVE: Meta-analyses of epidemiologic studies have suggested that metformin may reduce cancer incidence, but randomized controlled trials did not support this hypothesis. RESEARCH DESIGN AND METHODS A retrospective cohort study, Clinical Practice Research Datalink, was designed to investigate the association between use of metformin compared with other antidiabetes medications and cancer risk by emulating an intention-to-treat analysis as in a trial. A total of 95,820 participants with type 2 diabetes who started taking metformin and other oral antidiabetes medications within 12 months of their diagnosis (initiators) were followed up for first incident cancer diagnosis without regard to any subsequent changes in pharmacotherapy. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HR) and 95% CI. RESULTS: A total of 51,484 individuals (54%) were metformin initiators and 18,264 (19%) were sulfonylurea initiators, and 3,805 first incident cancers were diagnosed during a median follow-up time of 5.1 years. Compared with initiators of sulfonylurea, initiators of metformin had a similar incidence of total cancer (HR 0.96; 95% CI 0.89-1.04) and colorectal (HR 0.92; 95% CI 0.76-1.13), prostate (HR 1.02; 95% CI 0.83-1.25), lung (HR 0.85; 95% CI 0.68-1.07), or postmenopausal breast (HR 1.03; 95% CI 0.82-1.31) cancer or any other cancer. CONCLUSIONS: In this large study, individualswith diabetes who usedmetformin had a similar risk of developing cancer compared with those who used sulfonylureas.
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U2 - 10.2337/dc14-0584
DO - 10.2337/dc14-0584
M3 - Article
C2 - 24898303
AN - SCOPUS:84906691535
SN - 0149-5992
VL - 37
SP - 2522
EP - 2532
JO - Diabetes care
JF - Diabetes care
IS - 9
ER -