the impact of breast cancer on physical activity from midlife to early older adulthood and predictors of change post-diagnosis

To examine physical activity (pa) patterns from pre- to post-diagnosis, and compare these changes to women without breast cancer. to determine pre-diagnosis predictors of pa change, post-diagnosis, in breast cancer survivors (bcs). data were from 2314 study of women’s health across the nation (swan) participants, average age of 46.4 ± 2.7 years at baseline (1996–1997). in pink swan, 151 women who reported an incident breast cancer diagnosis over 20 years were classified as bcs; the remaining 2163 women were controls. loess plots and linear mixed models were used to illustrate and compare pa changes (sports/exercise [primary measure] and total pa) from pre- to post-diagnosis (or corresponding period) in bcs versus controls. adjusted linear regression models were used to determine pre-diagnosis predictors of at-risk post-diagnosis pa change patterns (consistently low and decreased pa). no differences in pre- to post-diagnosis pa (or corresponding period) were observed in bcs versus controls. among bcs, the odds of at-risk post-diagnosis pa change patterns was 2.50 (95% ci 0.96–6.48) times higher for those who reported sleep problems at ≥ 50% (compared to 0%) of pre-diagnosis visits and 3.49 (95% ci 1.26–9.65) times higher for those who were overweight or obese at all (compared to no) pre-diagnosis visits. no other statistically significant predictors were noted. age-related declines in pa were not amplified by a breast cancer diagnosis. given the beneficial role of pa across the cancer control continuum, efforts to increase or maintain adequate pa, post-diagnosis, should be continued. while age-related physical activity declines were not amplified breast cancer diagnosis, efforts to identify breast cancer survivors at increased risk for post-diagnosis physical activity declines (or maintenance of low activity) be a high-yield strategy to improve prognosis and quality of life.