TY - JOUR
T1 - Postmenopausal Breast Cancer and Physical Function Change
T2 - A Difference-in-Differences Analysis
AU - Michael, Yvonne L.
AU - Wu, Chengyi
AU - Pan, Kathy
AU - Seguin-Fowler, Rebecca A.
AU - Garcia, David O.
AU - Zaslavsky, Oleg
AU - Chlebowski, Rowan T.
N1 - Funding Information:
The Women's Health Initiative program is supported by the National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, through contracts N01WH22110, 24152, 32100‐2, 32105‐6, 32108‐9, 32111‐13, 32115, 32118 to 32119, 32122, 42107‐26, 42129‐32, and 44221.
Funding Information:
We thank the Women's Health Initiative investigators and staff and the trial participants for their outstanding dedication and commitment. The corresponding author has listed everyone who contributed to the work and has obtained written consent from all contributors who are not authors and are named in the Acknowledgments section. The Women's Health Initiative program is supported by the National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, through contracts N01WH22110, 24152, 32100-2, 32105-6, 32108-9, 32111-13, 32115, 32118 to 32119, 32122, 42107-26, 42129-32, and 44221. Dr Chlebowski reported being a consultant for Astra-Zeneca, Novartis, Amgen, and Genentech and receiving honorarium from Novartis and AstraZeneca. Y.L.M. led the overall study and designed the analysis strategy. C.W. executed the analysis. Y.L.M. and C.W. wrote the manuscript. D.G., R.S., C.W., O.Z., R.T.C., and K.P. provided critical review of the manuscript for important intellectual content, and all authors approved the final version of the article. R.T.C. collected the data and obtained study funding. The Women's Health Initiative (WHI) project office at the National Heart, Lung, and Blood Institute (NHLBI), which was the sponsor, had a role in the design and conduct of the study; interpretation of the data; review and approval of the manuscript; and decision to submit the manuscript for publication. Decisions concerning the above, as well as data collection, management, and analysis, resided with committees composed of WHI investigators and included NHLBI representatives. Program Office: (National Heart, Lung, and Blood Institute, Bethesda, MD) Jacques Roscoe, Shari Ludlum, Joan McGowan, Leslie Ford, and Nancy Geller. Clinical Coordinating Center: (Fred Hutchinson Cancer Research Center, Seattle, WA) Garnet Anderson, Ross Prentice, Andrea LaCroix, and Charles Kopperberg. Investigators and Academic Centers: (Brigham and Women's Hospital, Harvard Medical School, Boston, MA) JoAnn E. Manson; (MedStar Health Research Institute/Howard University, Washington, DC) Barbara V. Howard; (Stanford Prevention Research Center, Stanford, CA) Marcia L. Stefanick; (The Ohio State University, Columbus, OH) Rebecca Jackson; (University of Arizona, Tucson/Phoenix, AZ) Cynthia A. Thompson; (University at Buffalo, Buffalo, NY) Jean Wactawski-Wende; (University of Florida, Gainesville/Jacksonville, FL) Marian Limacher; (University of Iowa, Iowa City/Davenport, IA) Robert Wallace; (University of Pittsburgh, Pittsburgh, PA) Lewis Kuller; (City of Hope National Medical Center, Duarte, CA) Rowan T. Chlebowski; (Wake Forest University School of Medicine, Winston-Salem, NC) Sally Shumaker. Additional information: A full list of all the investigators who have contributed to Women's. Health Initiative science appears at: https://www.whi.org/researchers/SitePages/WHI%20Investigators.aspx
Publisher Copyright:
© 2020 The American Geriatrics Society
PY - 2020/5/1
Y1 - 2020/5/1
N2 - BACKGROUND/OBJECTIVES: While breast cancer and associated therapies can influence physical function (PF), findings for breast cancer's effects on PF among postmenopausal women are not consistent. This research evaluates the effect of breast cancer on change in PF. DESIGN: Longitudinal cohort study analyzed using difference-in-differences (DID) method to compare the changes in PF over time between women with and without breast cancer, by invasive status, stage, and age. SETTING AND PARTICIPANTS: Women's Health Initiative participants, aged 50 to 79 years at baseline, with four completed functional status assessments were eligible for inclusion (mean age = 62.1 ± 6.9 years). Women with breast cancer diagnosed between the 3rd and 11th enrollment year (n = 1636) were compared to women without breast cancer (n = 35 660). MEASUREMENTS: PF was measured using the Medical Outcomes Study Short Form 36 at baseline and years 3, 11, and 12. RESULTS: Compared with women without breast cancer, women with breast cancer experienced greater PF decline (P <.0001), after adjustment for age, race, education, income, study/trial arm, and body mass index. Overall, functional declines were greatest among women with invasive breast cancer (DID = −4.87; 95% confidence interval = −7.12 to −2.62). In stratified analyses, the breast cancer effect on PF was greater among women in older age groups. CONCLUSION: Women diagnosed with breast cancer experienced a significant decline in PF beyond what is observed in typical aging in this cohort. To optimally address survivorship issues, disease sequelae need to be distinguished from normal aging in studies incorporating a cancer-free comparison group. J Am Geriatr Soc 68:1029–1036, 2020.
AB - BACKGROUND/OBJECTIVES: While breast cancer and associated therapies can influence physical function (PF), findings for breast cancer's effects on PF among postmenopausal women are not consistent. This research evaluates the effect of breast cancer on change in PF. DESIGN: Longitudinal cohort study analyzed using difference-in-differences (DID) method to compare the changes in PF over time between women with and without breast cancer, by invasive status, stage, and age. SETTING AND PARTICIPANTS: Women's Health Initiative participants, aged 50 to 79 years at baseline, with four completed functional status assessments were eligible for inclusion (mean age = 62.1 ± 6.9 years). Women with breast cancer diagnosed between the 3rd and 11th enrollment year (n = 1636) were compared to women without breast cancer (n = 35 660). MEASUREMENTS: PF was measured using the Medical Outcomes Study Short Form 36 at baseline and years 3, 11, and 12. RESULTS: Compared with women without breast cancer, women with breast cancer experienced greater PF decline (P <.0001), after adjustment for age, race, education, income, study/trial arm, and body mass index. Overall, functional declines were greatest among women with invasive breast cancer (DID = −4.87; 95% confidence interval = −7.12 to −2.62). In stratified analyses, the breast cancer effect on PF was greater among women in older age groups. CONCLUSION: Women diagnosed with breast cancer experienced a significant decline in PF beyond what is observed in typical aging in this cohort. To optimally address survivorship issues, disease sequelae need to be distinguished from normal aging in studies incorporating a cancer-free comparison group. J Am Geriatr Soc 68:1029–1036, 2020.
KW - breast cancer
KW - difference in differences
KW - longitudinal
KW - physical function
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U2 - 10.1111/jgs.16323
DO - 10.1111/jgs.16323
M3 - Article
C2 - 31977067
AN - SCOPUS:85078799725
VL - 68
SP - 1029
EP - 1036
JO - Journal of the American Geriatrics Society
JF - Journal of the American Geriatrics Society
SN - 0002-8614
IS - 5
ER -