title: Anthropometric factors, physical activity, and breast cancer risk in relation to hormone receptor and menopausal status in Japanese women: a case-control study.
abstract: OBJECTIVE
  The associations between anthropometric factors, physical activity (PA), and breast cancer risk in terms of estrogen-receptor/progesterone-receptor (ER/PgR) status have been unclear in Japanese women. This case-control study was designed to evaluate these associations.
  
  
  METHODS
  From among female patients aged 30 years and over admitted to a single hospital in Japan between 1997 and 2009, 1,017 breast cancer cases (538ER+/PgR+, 125ER+/PgR-, 23 ER-/PgR+, 249 ER-/PgR-, and 82 missing) and 2,902 controls were selected. Height, weight, body mass index (BMI) (kg/m(2)), and time spent exercising (hours/week) were assessed using a self-administered questionnaire. Polytomous logistic regression analysis and tests for heterogeneity across ER+/PgR+ and ER-/PgR- were conducted.
  
  
  RESULTS
  Higher BMI was associated with a higher risk of ER+/PgR+ cancer among women overall [odds ratio (OR) = 2.41, 95 % confidence interval (CI) 1.37-4.23 for BMI ≥30.0; P(trend) = 0.0001] and postmenopausal women (OR = 6.24, 95 % CI 2.68-14.53 for BMI ≥30.0; P trend < 0.0001). A longer time spent exercising (more than 5 h/week) showed a decreased risk for any type of breast cancer among overall and pre- and postmenopausal women, although this did not reach statistical significance. Height was not associated with any risk.
  
  
  CONCLUSIONS
  Higher BMI is associated with an increased risk of ER+/PgR+ cancer among women overall and postmenopausal women. PA might be associated with a decreased risk of any type. To prevent breast cancer, weight control and PA are important.
authors.affiliation: Division of Community Health, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kawai
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kakugawa
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Nishino
authors.forename: Yohei
authors.initials: Y
authors.lastname: Hamanaka
authors.forename: Noriaki
authors.initials: N
authors.lastname: Ohuchi
authors.forename: Yuko
authors.initials: Y
authors.lastname: Minami
mesh_terms: D000328:Adult; D000886:Anthropometry; D044466:Asian People; D015992:Body Mass Index; D001835:Body Weight; D001943:Breast Neoplasms / Q000208:ethnology* / Q000503:physiopathology; D016022:Case-Control Studies; D015444:Exercise; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D016017:Odds Ratio; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D018570:Risk Assessment
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone