TY - JOUR
T1 - Effects of exercise in breast cancer patients: implications of the trials within cohorts (TwiCs) design in the UMBRELLA Fit trial
AU - Gal, Roxanne
AU - Monninkhof, Evelyn M.
AU - van Gils, Carla H.
AU - Groenwold, Rolf H. H.
AU - Elias, Sjoerd G.
AU - van den Bongard, Desirée H. J. G.
AU - Peeters, Petra H. M.
AU - Verkooijen, Helena M.
AU - May, Anne M.
N1 - Funding Information:
This work was supported by a Veni grant from the The Netherlands Organisation for Health Research and Development (ZonMw 016.156.050). In addition, funding was provided by the department of Radiotherapy, Imaging Division of the University Medical Center Utrecht (UMCU), and the department of Clinical Epidemiology, Julius Center for Health Sciences and Primary Care, UMCU.
Funding Information:
The authors thank the study team of the UMBRELLA cohort at the department of Radiotherapy, Division of Imaging and Oncology, and Julius Center for Health Sciences and Primary Care of the University Medical Center Utrecht (UMCU) for running the cohort and collecting the data. The authors also thank the Department of Rehabilitation, Physical Therapy Science and Sports, University Medical Center Utrecht (UMCU) for the collaboration and their assistance.
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/11
Y1 - 2021/11
N2 - Purpose: The Trials within Cohorts (TwiCs) design aims to overcome problems faced in conventional RCTs. We evaluated the TwiCs design when estimating the effect of exercise on quality of life (QoL) and fatigue in inactive breast cancer survivors. Methods: UMBRELLA Fit was conducted within the prospective UMBRELLA breast cancer cohort. Patients provided consent for future randomization at cohort entry. We randomized inactive patients 12–18 months after cohort enrollment. The intervention group (n = 130) was offered a 12-week supervised exercise intervention. The control group (n = 130) was not informed and received usual care. Six-month exercise effects on QoL and fatigue as measured in the cohort were analyzed with intention-to-treat (ITT), instrumental variable (IV), and propensity scores (PS) analyses. Results: Fifty-two percent (n = 68) of inactive patients accepted the intervention. Physical activity increased in patients in the intervention group, but not in the control group. We found no benefit of exercise for dimensions of QoL (ITT difference global QoL: 0.8, 95% CI = − 2.2; 3.8) and fatigue, except for a small beneficial effect on physical fatigue (ITT difference: − 1.1, 95% CI = − 1.8; − 0.3; IV: − 1.9, 95% CI = − 3.3; − 0.5, PS: − 1.2, 95% CI = − 2.3; − 0.2). Conclusion: TwiCs gave insight into exercise intervention acceptance: about half of inactive breast cancer survivors accepted the offer and increased physical activity levels. The offer resulted in no improvement on QoL, and a small beneficial effect on physical fatigue. Trial registration: Netherlands Trial Register (NTR5482/NL.52062.041.15), date of registration: December 07, 2015.
AB - Purpose: The Trials within Cohorts (TwiCs) design aims to overcome problems faced in conventional RCTs. We evaluated the TwiCs design when estimating the effect of exercise on quality of life (QoL) and fatigue in inactive breast cancer survivors. Methods: UMBRELLA Fit was conducted within the prospective UMBRELLA breast cancer cohort. Patients provided consent for future randomization at cohort entry. We randomized inactive patients 12–18 months after cohort enrollment. The intervention group (n = 130) was offered a 12-week supervised exercise intervention. The control group (n = 130) was not informed and received usual care. Six-month exercise effects on QoL and fatigue as measured in the cohort were analyzed with intention-to-treat (ITT), instrumental variable (IV), and propensity scores (PS) analyses. Results: Fifty-two percent (n = 68) of inactive patients accepted the intervention. Physical activity increased in patients in the intervention group, but not in the control group. We found no benefit of exercise for dimensions of QoL (ITT difference global QoL: 0.8, 95% CI = − 2.2; 3.8) and fatigue, except for a small beneficial effect on physical fatigue (ITT difference: − 1.1, 95% CI = − 1.8; − 0.3; IV: − 1.9, 95% CI = − 3.3; − 0.5, PS: − 1.2, 95% CI = − 2.3; − 0.2). Conclusion: TwiCs gave insight into exercise intervention acceptance: about half of inactive breast cancer survivors accepted the offer and increased physical activity levels. The offer resulted in no improvement on QoL, and a small beneficial effect on physical fatigue. Trial registration: Netherlands Trial Register (NTR5482/NL.52062.041.15), date of registration: December 07, 2015.
KW - Breast cancer
KW - Fatigue
KW - Physical activity
KW - Quality of life
KW - Trials within cohorts
KW - TwiCs
UR - https://www.scopus.com/pages/publications/85113344992
U2 - 10.1007/s10549-021-06363-9
DO - 10.1007/s10549-021-06363-9
M3 - Article
C2 - 34427806
SN - 0167-6806
VL - 190
SP - 89
EP - 101
JO - Breast cancer research and treatment
JF - Breast cancer research and treatment
IS - 1
ER -
SDG 3 Good Health and Well-being