Eric S Orwoll1, Terri Blackwell2, Steven R Cummings2,3, Jane A Cauley4, Nancy E Lane5, Andrew R Hoffman6, Andrew J Burghardt7, William J Evans8, Peggy M Cawthon2,3. 1. Bone and Mineral Unit, School of Medicine, Oregon Health & Science University, Portland, USA. 2. California Pacific Medical Center Research Institute, San Francisco, USA. 3. Department of Epidemiology and Biostatistics, University of California San Francisco, USA. 4. Department of Epidemiology, University of Pittsburgh, Graduate School of Public Health, Pennsylvania, USA. 5. Department of Medicine and Center for Musculoskeletal Health, University of California Davis, Sacramento, USA. 6. Department of Medicine, Stanford University, Palo Alto, California, USA. 7. Department of Radiology and Biomedical Imaging, University of California, San Francisco, USA. 8. Department of Nutritional Sciences and Toxicology, University of California, Berkeley, USA.
Abstract
BACKGROUND: Muscle mass declines with age, while body adiposity increases. Sarcopenic obesity has been proposed to be particularly deleterious. However, previous methods for estimating muscle mass have been inadequate, and the relative contributions of total body fat versus muscle fat to adverse outcomes have been unclear. METHOD: In a large cohort of older men (N = 1 017), we measured muscle mass (D3-creatine dilution), muscle density (high-resolution peripheral quantitative computed tomography in the diaphyseal tibia) as a proxy of muscle fat, and total body fat (dual-energy x-ray absorptiometry). We examined their associations with physical performance (walking speed, grip strength, chair stand time), the risk of mobility outcomes (mobility limitations, mobility disability), and the risk of death over ~5 years. RESULTS: In combined models, lower muscle mass and muscle density were independently associated with worse physical performance and the risk of adverse outcomes, while total body fat was minimally related to physical performance and not related to mobility outcomes or mortality. For example, the relative risks for mortality per 1 standardized unit increase in muscle density, muscle mass, and total body fat were 0.84 (95% confidence interval: 0.74, 0.96), 0.70 (0.57, 0.86), and 0.90 (0.64, 1.25), respectively. CONCLUSIONS: Muscle mass and muscle density were associated with physical performance and adverse outcomes, and had independent, additive effects. There was little additional contribution of total body fat.
BACKGROUND: Muscle mass declines with age, while body adiposity increases. Sarcopenic obesity has been proposed to be particularly deleterious. However, previous methods for estimating muscle mass have been inadequate, and the relative contributions of total body fat versus muscle fat to adverse outcomes have been unclear. METHOD: In a large cohort of older men (N = 1 017), we measured muscle mass (D3-creatine dilution), muscle density (high-resolution peripheral quantitative computed tomography in the diaphyseal tibia) as a proxy of muscle fat, and total body fat (dual-energy x-ray absorptiometry). We examined their associations with physical performance (walking speed, grip strength, chair stand time), the risk of mobility outcomes (mobility limitations, mobility disability), and the risk of death over ~5 years. RESULTS: In combined models, lower muscle mass and muscle density were independently associated with worse physical performance and the risk of adverse outcomes, while total body fat was minimally related to physical performance and not related to mobility outcomes or mortality. For example, the relative risks for mortality per 1 standardized unit increase in muscle density, muscle mass, and total body fat were 0.84 (95% confidence interval: 0.74, 0.96), 0.70 (0.57, 0.86), and 0.90 (0.64, 1.25), respectively. CONCLUSIONS: Muscle mass and muscle density were associated with physical performance and adverse outcomes, and had independent, additive effects. There was little additional contribution of total body fat.
Authors: Christine G Lee; Edward J Boyko; Carrie M Nielson; Marcia L Stefanick; Douglas C Bauer; Andrew R Hoffman; Thuy-Tien L Dam; Jodi A Lapidus; Peggy Mannen Cawthon; Kristine E Ensrud; Eric S Orwoll Journal: J Am Geriatr Soc Date: 2011-02-02 Impact factor: 5.562
Authors: Peggy M Cawthon; Kathleen M Fox; Shravanthi R Gandra; Matthew J Delmonico; Chiun-Fang Chiou; Mary S Anthony; Paolo Caserotti; Stephen B Kritchevsky; Anne B Newman; Bret H Goodpaster; Suzanne Satterfield; Steven R Cummings; Tamara B Harris Journal: J Am Geriatr Soc Date: 2011-05 Impact factor: 5.562
Authors: Jane A Cauley; Andrew J Burghardt; Stephanie L Harrison; Peggy M Cawthon; Ann V Schwartz; Elizabeth Barrett Connor; Kristine E Ensrud; Lisa Langsetmo; Sharmila Majumdar; Eric Orwoll Journal: J Bone Miner Res Date: 2018-06-12 Impact factor: 6.741
Authors: Peggy M Cawthon; Eric S Orwoll; Katherine E Peters; Kristine E Ensrud; Jane A Cauley; Deborah M Kado; Marcia L Stefanick; James M Shikany; Elsa S Strotmeyer; Nancy W Glynn; Paolo Caserotti; Mahalakshmi Shankaran; Marc Hellerstein; Steven R Cummings; William J Evans Journal: J Gerontol A Biol Sci Med Sci Date: 2019-05-16 Impact factor: 6.053
Authors: Jesse Zanker; Sheena Patel; Terri Blackwell; Kate Duchowny; Sharon Brennan-Olsen; Steven R Cummings; William J Evans; Eric S Orwoll; David Scott; Sara Vogrin; Jane A Cauley; Gustavo Duque; Peggy M Cawthon Journal: J Am Med Dir Assoc Date: 2020-05-04 Impact factor: 4.669
Authors: William J Evans; Marc Hellerstein; Eric Orwoll; Steve Cummings; Peggy M Cawthon Journal: J Cachexia Sarcopenia Muscle Date: 2019-03-21 Impact factor: 12.910
Authors: Kate A Duchowny; Katherine E Peters; Steven R Cummings; Eric S Orwoll; Andrew R Hoffman; Kristine E Ensrud; Jane A Cauley; William J Evans; Peggy M Cawthon Journal: J Cachexia Sarcopenia Muscle Date: 2019-10-17 Impact factor: 12.910
Authors: Jesse Zanker; Terri Blackwell; Sheena Patel; Kate Duchowny; Sharon Brennan-Olsen; Steven R Cummings; William J Evans; Eric S Orwoll; David Scott; Sara Vogrin; Gustavo Duque; Peggy M Cawthon Journal: Exp Gerontol Date: 2022-01-29 Impact factor: 4.032