B.A. Colgate University, 2003
M.Phil. University of Cambridge (Darwin College), 2006
Ph.D. University of Cambridge (Darwin College), 2009
Year Medical Student
Michael Leitzmann, M.D., Dr. PH; Nick Wareham, MBBS, Ph.D.;
Ulf Ekelund, Ph.D.
Department: National Cancer Institute; MRC Epidemiology
Graduate Program: Epidemiology
Physical activity and postmenopausal breast cancer risk in
the NIH-AARP Diet and Health study
Dr. Michael Leitzmann, Division of Cancer Epidemiology &
M. Peters,1,3 Arthur Schatzkin,1 Gretchen
L. Gierach,2,5 Steven C. Moore,1 James
V. Lacey, Jr.,2 Nicholas J. Wareham,3 Ulf Ekelund,3
Albert R. Hollenbeck,4 and Michael F. Leitzmann6
Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National
Cancer Institute, NIH, Bethesda, MD
2Hormonal and Reproductive Epidemiology Branch, Division
of Cancer Epidemiology
and Genetics, National Cancer Institute, NIH, Bethesda, MD.
3MRC Epidemiology Unit, Institute of Metabolic Science, Cambridge,
4AARP, Washington, DC.
5Cancer Prevention Fellowship Program, Office of Preventive
Cancer Institute, NIH, DHHS, Bethesda, MD.
6Regensburg University Medical Center, Regensburg, Germany
Breast cancer is recognized as the most common cancer affecting U.S.
women. Among the few modifiable risk factors for breast cancer, a high
versus low level of physical activity has been consistently associated
with 20-40% reduced risk of postmenopausal breast cancer. However, it
is unclear whether this association varies across breast cancer tumor
subtypes or is modified by reproductive and lifestyle factors.
We examined the association of physical activity with postmenopausal
breast cancer risk in 182,862 U.S. women in the NIH-AARP Diet and Health
Study cohort. Physical activity was assessed by self-report at baseline
(1995-1996), and 6,609 incident breast cancers were identified through
December 31, 2003. Cox regression was used to estimate the relative
risk (RR) and 95% confidence intervals (95%CI) of postmenopausal breast
cancer overall and by tumor characteristics. Effect modification by
select reproductive and lifestyle factors was also explored.
In multivariate models, physical activity was associated with reduced
breast cancer risk, and the most active women experienced a 13% lower
risk than inactive women (RR=0.87; 95%CI:0.81,0.95). This inverse relationship
was not modified by tumor stage or histology, but was suggestively stronger
for estrogen receptor (ER)-negative than for ER-positive breast tumors.
The relationship was more pronounced among women who had never used
menopausal hormone therapy and women with a family history of breast
cancer, and also appeared stronger for overweight/obese women.
A high level of physical activity was associated with reduced postmenopausal
breast cancer risk, particular to ER-negative tumors. These results,
along with heterogeneity in the physical activity-breast cancer relationship
for subgroups of menopausal hormone therapy use, indicate that physical
activity likely operates via estrogen-independent and estrogenic mechanisms
to influence breast cancer risk.
(pre-MSTP publications indicated with an *)
*Peters TM, et al. (on behalf of the InterAct Consortium).
Validity of a short questionnaire to assess physical activity in 10
European countries. European Journal of Epidemiology. 2012 Jan; 27(1):
TM, S Brage, K Westgate, et al. The InterAct Consortium: Validity
of the short European Prospective Investigation into Cancer and Nutrition
(EPIC) Questionnaire to assess physical activity in 10 European countries.
XO Shu, SC Moore, et al. (2010). Validity of a physical activity questionnaire
in Shanghai. Medicine and Science in Sports and Exercise. 42(12):2222-30.
SC Moore, YB Xiang, et al. (2010). Accelerometer-measured physical activity
in Chinese adults. American Journal of Preventive Medicine,
TM, A Schatzkin, GL Gierach, SC Moore, JV Lacey Jr, NJ Wareham,
U Ekelund, AR Hollenbeck, MF Leitzmann. (2009). Physical activity and
postmenopausal breast cancer risk in the NIH-AARP Diet and Health study.
SC, TM Peters, J Ahn, et al. (2009). Age-specific physical
activity and prostate cancer risk among white men and black men. Cancer.
TM, SC Moore, GL Gierach, et al. (2009). Intensity and timing
of physical activity in relation to postmenopausal breast cancer risk:
the prospective NIH-AARP Diet and Health Study. BMC Cancer,
SC, TM Peters, J Ahn, Y Park, A Schatzkin, D Albanes,
R Ballard-Barbash, A Hollenbeck, MF Leitzmann. (2008). Physical activity
in relation to total, advanced, and fatal prostate cancer. CEBP.
MF, SC Moore, TM Peters, JV Lacey Jr, A Schatzkin,
C Schairer, LA Brinton, D Albanes. (2008). Prospective study of physical
activity and risk of postmenopausal breast cancer. Cancer Res.
*Lipska B, T Peters, TM Hyde, N Halim, C Horowitz,
S Mitkus, C Shannon-Weickert, M Matsumoto, A Sawa, R Straub, R Vakkalanka,
MM Herman, DR Weinberger, JE Kleinman. (2006). Expression of DISC1 binding
partners is reduced in schizophrenia and associated with DISC1 SNPs.
Human Molecular Genetics. 15(8):1245-1258.
TM, U Ekelund, MF Leitzmann, D Easton, R Warren, R Luben, S
Bingham, KT Khaw, NJ Wareham. (2007). Physical Activity and Mammographic
Breast Density in the EPIC-Norfolk Cohort Study. American Journal
of Epidemiology. 167(5):579-585.