title: [Risk factors in the development of breast cancer, state of Mexico].
abstract: BACKGROUND
  Breast cancer is one of the most frequent diseases in women today, and its social impact is devastating. The risk factors focused on in recent research are mainly hormonal, genetic, and environmental though toxic habits, overweight, and obesity have also been studied. In contrast, protective factors against breast cancer include breastfeeding and daily exercise.
  
  
  OBJECTIVE
  To ascertain the risk factors for the women with breast cancer in our study sample.
  
  
  METHODS
  A study of cases and controls was performed on 115 women diagnosed with breast cancer and on 115 healthy women, who had been patients at the National Cancer Institute ISSEMYM in Mexico from January to December 2011. Information was collected from the women in the sample pertaining to their family history of cancer, personal background, life style, and body mass index (BMI). Breast cancer risk was estimated with multivariate logistic regression models and the chi-square test.
  
  
  RESULTS
  It was found that there was a greater risk of breast cancer in overweight or obese women who did not do any physical exercise and either who had breastfed their children for a very short time or who had not breastfed them at all. No significant differences were found between breast cancer and toxic habits.
  
  
  CONCLUSIONS
  The results of our study found a direct relation between breast cancer and overweight, obesity, and physical inactivity. Breastfeeding during the first months of the baby's life was found to be a protective factor against breast cancer.
authors.affiliation: Departamento de Enfermería, Facultad de Ciencias de la Salud, Universidad de Granada, Granada, España. mariajaguilar@telefonica.net
authors.forename: M J
authors.initials: MJ
authors.lastname: Aguilar Cordero
authors.forename: M
authors.initials: M
authors.lastname: Neri Sánchez
authors.forename: C A
authors.initials: CA
authors.lastname: Padilla López
authors.forename: M L
authors.initials: ML
authors.lastname: Pimentel Ramírez
authors.forename: A
authors.initials: A
authors.lastname: García Rillo
authors.forename: A M
authors.initials: AM
authors.lastname: Sánchez López
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001942:Breast Feeding; D001943:Breast Neoplasms / Q000453:epidemiology*; D002648:Child; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D050177:Overweight / Q000453:epidemiology; D011629:Puberty, Precocious / Q000453:epidemiology; D012307:Risk Factors; D055815:Young Adult