Diabetes and breast cancer risk: a meta-analysis

• Published in: Breast cancer research and treatment Vol. 107; no. 9; pp. 1608 - 1617
• Main Authors: Boyle, P, Boniol, M, Koechlin, A, Robertson, C, Valentini, F, Coppens, K, Fairley, L-L, Zheng, T, Zhang, Y, Pasterk, M, Smans, M, Curado, M P, Mullie, P, Gandini, S, Bota, M, Bolli, G B, Rosenstock, J, Autier, P
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 23.10.2012; Nature Publishing Group; Springer Verlag
• Subjects: 692/308/2779/174; 692/699/2743/137/773; 692/699/67/1347; Age; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Body mass; Body Mass Index; Breast cancer; Breast Neoplasms - epidemiology; Breast Neoplasms - etiology; Cancer; Cancer Research; Diabetes mellitus; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - epidemiology; Diabetes. Impaired glucose tolerance; Drug Resistance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Epidemiology; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; Humans; Life Sciences; Medical sciences; Molecular Medicine; Oncology; Risk Assessment; Risk Factors; Santé publique et épidémiologie; Tumors; meta-analysis; breast cancer; diabetes; body mass index; Endocrinopathy; Breast disease; Diabetes mellitus; Breast cancer; Malignant tumor; Risk analysis; Metaanalysis; Mammary gland diseases; Body mass index; Cancerology; Cancer; Type 2/complications/epidemiology Female Humans Risk Assessment Risk Factors; Body Mass Index Breast Neoplasms/epidemiology/etiology Diabetes Mellitus
• ISSN: 0007-0920; 1532-1827; 0167-6806; 1532-1827; 1573-7217
• DOI: 10.1038/bjc.2012.414

Background: The potential of an increased risk of breast cancer in women with diabetes has been the subject of a great deal of recent research. Methods: A meta-analysis was undertaken using a random effects model to investigate the association between diabetes and breast cancer risk. Results: Thirty-nine independent risk estimates were available from observational epidemiological studies. The summary relative risk (SRR) for breast cancer in women with diabetes was 1.27 (95% confidence interval (CI), 1.16–1.39) with no evidence of publication bias. Prospective studies showed a lower risk (SRR 1.23 (95% CI, 1.12–1.35)) than retrospective studies (SRR 1.36 (95% CI, 1.13–1.63)). Type 1 diabetes, or diabetes in pre-menopausal women, were not associated with risk of breast cancer (SRR 1.00 (95% CI, 0.74–1.35) and SRR 0.86 (95% CI, 0.66–1.12), respectively). Studies adjusting for body mass index (BMI) showed lower estimates (SRR 1.16 (95% CI, 1.08–1.24)) as compared with those studies that were not adjusted for BMI (SRR 1.33 (95% CI, 1.18–1.51)). Conclusion: The risk of breast cancer in women with type 2 diabetes is increased by 27%, a figure that decreased to 16% after adjustment for BMI. No increased risk was seen for women at pre-menopausal ages or with type 1 diabetes.