title: The effects of metformin on the survival of colorectal cancer patients with diabetes mellitus.
abstract: Metformin use has been associated with decreased cancer risk and mortality. However, the effects of metformin on clinical outcomes of colorectal cancer (CRC) are not defined. This study aimed to evaluate the association between metformin use and mortality of CRC in diabetic patients. We identified 595 patients who were diagnosed both CRC and diabetes mellitus. Patients were compared by two groups; 258 diabetic patients taking metformin and 337 diabetic patients not taking metformin. Patient's demographics, clinical characteristics, overall mortality and CRC-specific mortality were analyzed. After a median follow-up of 41 months, there were 71 total deaths (27.5%) and 55 CRC-specific deaths (21.3%) among 258 patients who used metformin, compared with 136 total deaths (40.4%) and 104 CRC-specific deaths (30.9%) among 337 patients who did not use metformin. Metformin use was associated with decreased overall mortality (p = 0.018) and CRC-specific mortality (p = 0.042) by univariate analysis. After adjustment for clinically relevant factors, metformin use showed lower risk of overall mortality (HR, 0.66; 95% CI 0.476-0.923; p = 0.015) and CRC-specific mortality (HR, 0.66; 95% CI 0.45-0.975; p = 0.037) in CRC patients with diabetes. Metformin use in CRC patients with diabetes is associated with lower risk of CRC-specific and overall mortality.
authors.affiliation: Department of Internal Medicine and Institute of Gastroenterology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jin Ha
authors.initials: JH
authors.lastname: Lee
authors.forename: Tae Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Soung Min
authors.initials: SM
authors.lastname: Jeon
authors.forename: Sung Pil
authors.initials: SP
authors.lastname: Hong
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Cheon
authors.forename: Won Ho
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000150:complications / Q000401:mortality*; D048909:Diabetes Complications; D003920:Diabetes Mellitus; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000627:therapeutic use*; D008875:Middle Aged; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D007004:Hypoglycemic Agents; D008687:Metformin