title: Prediabetes, diabetes, and risk of breast cancer: a case-control study.
abstract: OBJECTIVE
  Although underlying mechanisms have been described to account for the association between prediabetes and diabetes with breast cancer, reported results have been inconsistent. We undertook this study to determine whether prediabetes and diabetes are risk factors for breast cancer in Mexican women with no family history of breast cancer in the mother, daughters, or sisters.
  
  
  METHODS
  A case-control study was carried out during 2011-2013. "Case" referred to patients with a histopathological diagnosis of breast cancer (incident and primary cases) (n = 240); "controls" were those with a BI-RADS 1 or 2 mammography result (n = 406). Categorization of prediabetes and diabetes was based on self-reporting or fasting glucose and glycated hemoglobin blood sampling results. Reproductive and sociodemographic data were collected by interview. Odds ratios (ORs) and 95% confidence intervals (CI) were calculated using multivariate unconditional binary logistic regression analysis.
  
  
  RESULTS
  Prediabetes increased the risk of breast cancer in postmenopausal women (adjusted OR 2.08, 95% CI 1.10-3.96) as did diabetes (adjusted OR 2.85, 95% CI 1.55-5.26). A history of diabetes preceding breast cancer by ≥7 years and <7 years were both associated with an increased risk for breast cancer (adjusted OR 2.80, 95% CI 1.40-5.60 and 3.00, 95% CI 1.50-5.90, respectively).
  
  
  CONCLUSIONS
  This is the first study in Mexico evaluating prediabetes and diabetes as breast cancer risk factors in women with no first-degree relatives with breast cancer. Our findings suggest that women with prediabetes and diabetes should be considered a more vulnerable population for early breast cancer detection.
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud No. 34, Instituto Mexicano del Seguro Social, Centro Médico Nacional del Norte, Monterrey, N.L., México; Universidad Autónoma de Nuevo León, Facultad de Salud Pública y Nutrición, Monterrey, N.L., México. Electronic address: amsalinasm@intercable.net.
authors.forename: Ana María
authors.initials: AM
authors.lastname: Salinas-Martínez
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud No. 34, Instituto Mexicano del Seguro Social, Centro Médico Nacional del Norte, Monterrey, N.L., México.
authors.forename: Lillian Ivette
authors.initials: LI
authors.lastname: Flores-Cortés
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud No. 34, Instituto Mexicano del Seguro Social, Centro Médico Nacional del Norte, Monterrey, N.L., México.
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Cardona-Chavarría
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud No. 34, Instituto Mexicano del Seguro Social, Centro Médico Nacional del Norte, Monterrey, N.L., México.
authors.forename: Brenda
authors.initials: B
authors.lastname: Hernández-Gutiérrez
authors.affiliation: Unidad Médica de Alta Especialidad, Hospital de Ginecología y Obstetricia No. 23, Instituto Mexicano del Seguro Social, Monterrey, N.L., México.
authors.forename: Alberto
authors.initials: A
authors.lastname: Abundis
authors.affiliation: Unidad Médica de Alta Especialidad, Hospital de Ginecología y Obstetricia No. 23, Instituto Mexicano del Seguro Social, Monterrey, N.L., México.
authors.forename: Julia
authors.initials: J
authors.lastname: Vázquez-Lara
authors.affiliation: Coordinación de Planeación y Enlace Institucional, Instituto Mexicano del Seguro Social, Monterrey, N.L., México.
authors.forename: Eduardo Enrique
authors.initials: EE
authors.lastname: González-Guajardo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000209:etiology*; D016022:Case-Control Studies; D016001:Confidence Intervals; D048909:Diabetes Complications; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008800:Mexico; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011236:Prediabetic State / Q000150:complications*; D015995:Prevalence; D012307:Risk Factors; D057566:Self Report
keywords: Breast cancer; Case control studies; Diabetes; Prediabetes