Post-diagnosis physical activity and survival after breast cancer diagnosis: the Long Island Breast Cancer Study.
Physical activity (PA) is associated with physiological responses thought to beneficially affect survival after breast cancer diagnosis, yet few studies have considered the entire survivorship experience. Effects of post-diagnosis activity on survival were examined in a cohort of 1,423 women diagnosed with in situ or invasive breast cancer in 1996-1997. Subjects were interviewed soon after diagnosis and again after approximately 5 years to assess breast cancer-related factors, including recreational PA before and after diagnosis. Date and cause of death through 2009 were determined from the National Death Index. Adjusted estimates were obtained using proportional hazards regression and a selection model to account for missing data. Survival was improved among women who were highly active after diagnosis (>9.0 MET h/week) compared to inactive women (0 MET h/week) for all-cause [hazard ratio (HR) (95 % credible interval): 0.33 (0.22, 0.48)] and breast cancer-specific mortality [HR: 0.27 (0.15, 0.46)]. The association of PA with overall mortality appeared stronger in the first 2 years after diagnosis [HR: 0.14 (0.03, 0.44)] compared to 2+ years since diagnosis [HR: 0.37 (0.25, 0.55)]. These findings show that post-diagnosis PA is associated with improved survival among women with breast cancer.
Department of Nutrition, University of North Carolina, CB#7461, Chapel Hill, NC, 27599-7461, USA, patrickb@email.unc.edu.
Patrick T
PT
Bradshaw
Joseph G
JG
Ibrahim
Nikhil
N
Khankari
Rebecca J
RJ
Cleveland
Page E
PE
Abrahamson
June
J
Stevens
Jessie A
JA
Satia
Susan L
SL
Teitelbaum
Alfred I
AI
Neugut
Marilie D
MD
Gammon
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011795:Surveys and Questionnaires; D015996:Survival Rate