title: Vigorous physical activity and risk of breast cancer in the African American breast cancer epidemiology and risk consortium.
abstract: The relationship between physical activity and breast cancer risk has been extensively studied among women of European descent, with most studies reporting inverse associations. However, data on American women of African ancestry (AA) and by tumor subtypes are sparse. Thus, we examined associations of vigorous exercise and breast cancer risk overall, and by estrogen receptor (ER) status, in the African American Breast Cancer Epidemiology and Risk Consortium. We pooled data from four large studies on 2482 ER+ cases, 1374 ER- cases, and 16,959 controls. Multivariable logistic regression was used to compute odds ratios (OR) and 95 % confidence intervals (CI) for the risk of breast cancer overall, and polytomous logistic regression was used to model the risk of ER+ and ER- cancer. Recent vigorous exercise was associated with a statistically significant, modestly decreased risk for breast cancer overall (OR 0.88, 95 % CI 0.81-0.96) and for ER+ cancer (OR 0.88, 95 % CI 0.80-0.98), but not for ER- cancer (OR 0.93, 95 % CI 0.82-1.06). Overall, there was no strong evidence of effect modification by age, menopausal status, body mass index, and parity. However, our data were suggestive of modification by family history, such that an inverse association was present among women without a family history but not among those with a relative affected by breast cancer. Results from this large pooled analysis provide evidence that vigorous physical activity is associated with a modestly reduced risk of breast cancer in AA women, specifically ER+ cancer.
authors: Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA. zhihong.gong@roswellpark.org.
authors: Zhihong
authors: http://orcid.org/0000-0003-1129-1774
authors: Z
authors: Gong
authors: Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA.
authors: Chi-Chen
authors: CC
authors: Hong
authors: Cancer Prevention and Control, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA.
authors: Elisa V
authors: EV
authors: Bandera
authors: Cancer Prevention and Control, Georgetown Lombardi Comprehensive Cancer Center, Washington, DC, USA.
authors: Lucile L
authors: LL
authors: Adams-Campbell
authors: Cancer Epidemiology, University of North Carolina, Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA.
authors: Melissa A
authors: MA
authors: Troester
authors: Cancer Epidemiology, University of Hawaii Cancer Center, Honolulu, HI, USA.
authors: Song-Yi
authors: SY
authors: Park
authors: Slone Epidemiology Center at Boston University, Boston, MA, USA.
authors: Kathryn A
authors: KA
authors: McInerney
authors: Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA.
authors: Gary
authors: G
authors: Zirpoli
authors: Cancer Epidemiology, University of North Carolina, Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA.
authors: Andrew F
authors: AF
authors: Olshan
authors: Slone Epidemiology Center at Boston University, Boston, MA, USA.
authors: Julie R
authors: JR
authors: Palmer
authors: Department of Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY, 14263, USA.
authors: Christine B
authors: CB
authors: Ambrosone
authors: Slone Epidemiology Center at Boston University, Boston, MA, USA.
authors: Lynn
authors: L
authors: Rosenberg
mesh_terms: D001741:Black or African American; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000208:ethnology / Q000378:metabolism; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D016017:Odds Ratio; D011960:Receptors, Estrogen / Q000378:metabolism*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
chemical_list: D011960:Receptors, Estrogen
keywords: African American women; Breast cancer; Subtype; Vigorous physical activity