Past recreational physical activity, body size, and all-cause mortality following breast cancer diagnosis: results from the breast cancer family registry

Abstract

Few studies have considered the joint association of body mass index (BMI) and physical activity, two modifiable factors, with all-cause mortality after breast cancer diagnosis. Women diagnosed with invasive breast cancer (n=4,153) between 1991 and 2000 were enrolled in the Breast Cancer Family Registry through population-based sampling in Northern California, USA; Ontario, Canada; and Melbourne and Sydney, Australia. During a median follow-up of 7.8 years, 725 deaths occurred. Baseline questionnaires assessed moderate and vigorous recreational physical activity and BMI prior to diagnosis. Associations with all-cause mortality were assessed using Cox proportional hazards regression, adjusting for established prognostic factors. Compared with no physical activity, any recreational activity during the three years prior to diagnosis was associated with a 34% lower risk of death (hazard ratio (HR) = 0.66, 95% confidence interval (CI): 0.51-0.85) for women with estrogen receptor (ER)-positive tumors, but not those with ERnegative tumors; this association did not appear to differ by race/ethnicity or BMI. Lifetime physical activity was not associated with all-cause mortality. BMI was positively associated with

Neighborhood influences on recreational physical activity and survival after breast cancer

“…Higher levels of physical activity have been associated with a 30 % reduction in mortality risk after breast cancer diagnosis [6], as well as reduced risk of recurrence, and improved quality of life and physical functioning [7]. We previously reported that any (vs. no) recreational activity during the 3 years before breast cancer diagnosis was associated with a 34 % lower risk of death for women with estrogen receptor-positive tumors [8]. …”

Physical activity and survival among Hispanic and non-Hispanic white long-term breast cancer survivors and population-based controls

“…Accumulating epidemiological evidence indicates that moderate to vigorous intensity levels of physical activity are positively associated with improved survival in women diagnosed with breast cancer [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. While the magnitude of estimates were similar, these studies differed in the timing of measured physical activity; some reported activity before breast cancer diagnosis [4, 8-10, 17, 18], others after diagnosis [5-7, 11, 12, 15, 16], and the remaining presented separate analyses for pre-and post-diagnostic levels [13,14].…”

“…Hispanic participants, when included, are few in number. Several studies have adjusted for ethnicity in analysis [4,5,9,13,14,18,16]; however, the Breast Cancer Family Registry, a multinational study of participants in the USA, Canada, and Australia, was the only previous study to present a subgroup analysis by ethnicity, including a small sample of Hispanic women (n= 148) diagnosed with estrogen receptor positive breast cancer [18]. Lastly, few studies have compared associations of physical activity with mortality in cases with a sample of population-based, matched controls.…”

Potential Mechanisms behind Physical Exercise vs. Epigenetic Regulation for Preventing Breast Cancer

“…In this review, we have summarized a collection of various population-based studies on breast cancer and PA, and compared the beneficial effect of exercise on cancer such as the cancer type, duration, intensity, and timing of exercise (before diagnosis, after diagnosis, or during treatment) ( Table 2) [76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91][92]. Numerous studies have suggested that PA prior to breast cancer diagnosis was significantly beneficial for the patient's treatment outcome and survival [76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91][92]. For example, a group of researchers performed a prospective cohort study in Germany which included 3,393 non-metastatic breast cancer patients: the mortality of breast cancer was significantly and inversely associated with prediagnosis recreational PA [77].…”

“…A populationbased sampling in the U.S., Canada, and Australia was investigated with follow-up for 7 -8 years, and showed that patients engaging in recreational activity during the 3 years prior to diagnosis had a 34% lower risk of cancer-related death. It was estimated that about 7.9% of Canadian patient cancer cases (breast, colon, endometrium, prostate, lung, and ovarian) were associated with physical inactivity, demonstrating that thousands of cancer cases may be prevented by following a healthy lifestyle which includes PA [85]. In a study from Norwegian Counties spanning from 1974 to 2005, 1,364 breast cancer patients were surveyed.…”