TY - JOUR
T1 - Evaluation of the Bidirectional Relations of Perceived Physical Fatigability and Physical Activity on Slower Gait Speed
AU - Qiao, Yujia (susanna)
AU - Gmelin, Theresa
AU - Renner, Sharon W.
AU - Boudreau, Robert M.
AU - Martin, Sarah
AU - Wojczynski, Mary K.
AU - Christensen, Kaare
AU - Andersen, Stacy L.
AU - Cosentino, Stephanie
AU - Santanasto, Adam J.
AU - Glynn, Nancy W.
N1 - Publisher Copyright:
© 2020 The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: [email protected].
PY - 2021/10/1
Y1 - 2021/10/1
N2 - Background: Lower physical activity levels and greater fatigability contribute independently to slower gait speed in older adults. To fully understand the bidirectional relations between physical activity and fatigability, and to inform potential intervention strategies, we examined whether physical activity or fatigability explains more of the other factor's association on slower gait speed. Methods: Two generations (probands and offspring) of older adults (N = 2079, mean age 73.0 ± 10.0 years, 54.2% women, 99.7% White) enrolled in the Long Life Family Study were assessed at Visit 2 (2014-2017). Self-reported physical activity was measured with the Framingham Physical Activity Index and perceived physical fatigability using the Pittsburgh Fatigability Scale. Statistical mediation analyses were conducted separately by generation with linear mixed-effect models accounting for family relatedness and adjusted for demographics, health conditions, and field center. Results: Greater perceived physical fatigability explained the association of lower physical activity on slower gait speed via a 22.5% attenuation of the direct association (95% confidence interval [CI]: 15.0%-35.2%) for the probands and 39.5% (95% CI: 22.8%-62.6%) for the offspring. Whereas lower physical activity explained the association of greater perceived fatigability on slower gait speed via a 22.5% attenuation of the direct association (95% CI: 13.4%-32.8%) for the probands and 6.7% (95% CI: 3.8%-15.4%) for the offspring. Conclusions: Our findings suggest that the impact of greater perceived physical fatigability on the association between lower physical activity and slower gait speed differs between younger-old and middle-to-oldest-old adults, indicating perceived physical fatigability as a potential mediator in the disablement pathway.
AB - Background: Lower physical activity levels and greater fatigability contribute independently to slower gait speed in older adults. To fully understand the bidirectional relations between physical activity and fatigability, and to inform potential intervention strategies, we examined whether physical activity or fatigability explains more of the other factor's association on slower gait speed. Methods: Two generations (probands and offspring) of older adults (N = 2079, mean age 73.0 ± 10.0 years, 54.2% women, 99.7% White) enrolled in the Long Life Family Study were assessed at Visit 2 (2014-2017). Self-reported physical activity was measured with the Framingham Physical Activity Index and perceived physical fatigability using the Pittsburgh Fatigability Scale. Statistical mediation analyses were conducted separately by generation with linear mixed-effect models accounting for family relatedness and adjusted for demographics, health conditions, and field center. Results: Greater perceived physical fatigability explained the association of lower physical activity on slower gait speed via a 22.5% attenuation of the direct association (95% confidence interval [CI]: 15.0%-35.2%) for the probands and 39.5% (95% CI: 22.8%-62.6%) for the offspring. Whereas lower physical activity explained the association of greater perceived fatigability on slower gait speed via a 22.5% attenuation of the direct association (95% CI: 13.4%-32.8%) for the probands and 6.7% (95% CI: 3.8%-15.4%) for the offspring. Conclusions: Our findings suggest that the impact of greater perceived physical fatigability on the association between lower physical activity and slower gait speed differs between younger-old and middle-to-oldest-old adults, indicating perceived physical fatigability as a potential mediator in the disablement pathway.
KW - Epidemiology
KW - Fatigue
KW - Physical function
KW - Physical performance
UR - http://www.scopus.com/inward/record.url?scp=85101668682&partnerID=8YFLogxK
U2 - 10.1093/gerona/glaa281
DO - 10.1093/gerona/glaa281
M3 - Article
C2 - 33170216
AN - SCOPUS:85101668682
SN - 1079-5006
VL - 76
SP - E237-E244
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
IS - 10
ER -