Background: Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, functional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods: Older adults with HF and reduced ejection fraction (n = 25, age 75 ± 7 years) were compared to 25 healthy age- and gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2peak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results: Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions: Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF.
|Original language||English (US)|
|Number of pages||8|
|Journal||Journal of Geriatric Cardiology|
|State||Published - 2016|
Bibliographical noteFunding Information:
The authors acknowledge primary support of the Department of Veterans Affairs Research and Development and additional support from the National Institute of Aging (NIA) Michigan Claude Pepper Older Americans Independence Center (AG08808 and AG024824). Dr. Hummel is supported by a K23 Mentored Patient-Oriented Career Development Award HL109176 from the National Heart Lung and Blood Institute (NHLBI). Dr. Alexander was a recipient of a K24 Mid-Career Investigator Award in Patient-Oriented Research AG109675 from NIA. Dr. Gretebeck was the recipient of an American Diabetes Association Junior Faculty Award (1-06-JF-20). The assistance of Nicole Osevala, Mark Hofmeyer, Becky Cleland, Diane Scarpace, Nancy Ambrose-Gallagher, Ravinder Goswami, and Eric Pear in participant recruitment, assessment, and data collection is gratefully acknowledged. The authors do not receive any financial benefit from the study results or funding sources.
©2016 JGC All rights reserved.
- Congestive heart failure
- Oxygen uptake
- The elderly