Role of Cardiorespiratory Fitness and Mitochondrial Oxidative Capacity in Reduced Walk Speed of Older Adults with Diabetes

Sofhia V Ramos; Giovanna Distefano; Li-Yung Lui; Peggy M Cawthon; Philip Kramer; Ian J Sipula; Fiona M Bello; Theresa Mau; Michael J Jurczak; Anthony J Molina; Erin E Kershaw; David J Marcinek; Eric Shankland; Frederico G S Toledo; Anne B Newman; Russell T Hepple; Stephen B Kritchevsky; Bret H Goodpaster; Steven R Cummings; Paul M Coen

doi:10.2337/db23-0827

Role of Cardiorespiratory Fitness and Mitochondrial Oxidative Capacity in Reduced Walk Speed of Older Adults with Diabetes

Diabetes. 2024 Mar 29:db230827. doi: 10.2337/db23-0827. Online ahead of print.

Authors

Sofhia V Ramos¹, Giovanna Distefano¹, Li-Yung Lui^{2

3}, Peggy M Cawthon^{2

3}, Philip Kramer⁴, Ian J Sipula⁵, Fiona M Bello⁵, Theresa Mau^{2

3}, Michael J Jurczak⁵, Anthony J Molina⁶, Erin E Kershaw⁵, David J Marcinek⁷, Eric Shankland⁷, Frederico G S Toledo⁵, Anne B Newman⁵, Russell T Hepple⁸, Stephen B Kritchevsky⁴, Bret H Goodpaster¹, Steven R Cummings^{2

3}, Paul M Coen¹

Affiliations

¹ Translational Research Institute, Advent Health, Orlando, Florida, USA.
² San Francisco Coordinating Center, California Pacific Medical Center Research Institute, San Francisco, California USA.
³ Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA.
⁴ Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
⁵ Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
⁶ Department of Medicine, University of California, San Diego, California, USA.
⁷ Department of Radiology, University of Washington School of Medicine, Seattle, Washington, USA.
⁸ Department of Physical Therapy, University of Florida, Gainesville, Florida, USA.

PMID: 38551899
DOI: 10.2337/db23-0827

Abstract

Cardiorespiratory fitness and mitochondrial oxidative capacity are associated with reduced walking speed in older adults. The impact of cardiorespiratory fitness and mitochondrial oxidative capacity on walking speed in older adults with diabetes has not been clearly defined. We examined differences in cardiorespiratory fitness and skeletal muscle mitochondrial oxidative capacity between older adults with and without diabetes as well as determine their relative contribution to slower walking speed in older adults with diabetes. Participants with diabetes (n=159) had lower cardiorespiratory fitness and mitochondrial respiration in permeabilized fiber bundles when compared to those without diabetes (n=717), following adjustments for covariates including BMI, chronic comorbid health conditions, and physical activity. 4-m and 400-m walking speeds were slower in those with diabetes. Mitochondrial oxidative capacity alone or combined with cardiorespiratory fitness mediated ∼20-70% of the difference in walk speed between older adults with and without diabetes. Additional adjustments with BMI and co-morbidities further explained the group differences in walk speed. Cardiorespiratory fitness and skeletal muscle mitochondrial oxidative capacity contribute to slower walking speeds in older adults with diabetes.