Endothelial Progenitor Cell Levels Predict Future Physical Function: An Exploratory Analysis From the VA Enhanced Fitness Study.
BACKGROUND
Levels of circulating progenitor cells (CPCs) are depleted with aging and chronic injury and are associated with level of physical functioning; however, little is known about the correlation of CPCs with longer-term measures of physical capabilities. We sought to determine the association of CPCs with future levels of physical function and with changes in physical function over time.


METHODS
CPCs were measured in 117 participants with impaired glucose tolerance in the Enhanced Fitness clinical trial based on the cell surface markers CD34 and CD133 and aldehyde dehydrogenase (ALDH) activity at baseline, 3 months, and 12 months. Physical function was assessed using usual and rapid gait speed, 6-minute walk distance, chair stand time, and SF-36 physical functioning score and reassessed at 3 and 12 months after clinical intervention.


RESULTS
Higher baseline levels of CD133(+), CD34(+), CD133(+)CD34(+), and ALDH(br) were each highly predictive of faster gait speed and longer distance walked in 6 minutes at both 3 and 12 months. These associations remained robust after adjustment for age, body mass index, baseline covariates, and inflammation and were independent of interventions to improve physical fitness. Further, higher CPC levels predicted greater improvements in usual and rapid gait speed over 1 year.


CONCLUSIONS
Baseline CPC levels are associated not only with baseline mobility but also with future physical function, including changes in gait speed. These findings suggest that CPC measurement may be useful as a marker of both current and future physiologic aging and functional decline.
Duke Clinical Research Institute, Department of Medicine, thomas.povsic@duke.edu.
Thomas J
TJ
Povsic
Claude D. Pepper Older Americans Independence Center, and Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina.
Richard
R
Sloane
Claude D. Pepper Older Americans Independence Center, and Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina.
Carl F
CF
Pieper
Geriatric Research, Education, and Clinical Center and Center for Health Services Research and Development, Durham Veterans Affairs Medical Center, Durham, North Carolina.
Megan P
MP
Pearson
Duke Clinical Research Institute, Department of Medicine.
Eric D
ED
Peterson
Department of Medicine, Claude D. Pepper Older Americans Independence Center, and Geriatric Research, Education, and Clinical Center and.
Harvey J
HJ
Cohen
Department of Medicine, Claude D. Pepper Older Americans Independence Center, and Geriatric Research, Education, and Clinical Center and Center for Health Services Research and Development, Durham Veterans Affairs Medical Center, Durham, North Carolina.
Miriam C
MC
Morey
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000444:Aldehyde Dehydrogenase / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D066026:Endothelial Progenitor Cells / Q000166:cytology* / Q000378:metabolism; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D016138:Walking / Q000502:physiology*
D015703:Antigens, CD; D015415:Biomarkers; D000444:Aldehyde Dehydrogenase
Aging; Endothelial progenitor cells; Physical function; Physical performance; Progenitor cells biology