title: Muscle fatigability and depressive symptoms in later life.
abstract: Fatigability is the degree to which performance decreases during a specific activity of a given intensity and duration. Depression is known to heighten subjective fatigue, but whether its association with physical fatigability is unknown. Further, whether fatigability is a precursor or risk factor for the development of subsequent depressive symptoms is also unclear.
  
  
  
  Data are from the Health Aging and Body Composition Study with fatigability assessed using isokinetic dynamometry of the knee extensors at year 3, and depressive symptoms ascertained longitudinally using the Center for Epidemiologic Studies Depression (CES-D) scale. The relationship between fatigability and depressive symptoms was evaluated using linear and Cox regression models.
  
  
  
  There was a significant cross-sectional association between fatigability and depressive symptomatology (β = -0.06, p = 0.02), after adjusting for demographic variables, medical comorbidities, cognition, gait speed, and physical activity levels. Greater fatigability was associated with greater adjusted scores on the 10-item CES-D (F2, 1695= 38.65, p < 0.001), with individuals with greater fatigability on average reporting an adjusted CES-D score 0.5 point greater than those individuals with higher levels of resistance to fatigability (mean of 70% or better; p < 0.001). Fatigability however was not associated with the development of depression at follow-up (p = 0.828).
  
  
  
  This study found an association between skeletal muscle fatigability and higher depressive symptoms in older adults, but no longitudinal association was identified. These findings suggest that age-related changes in energy capacity may affect the phenomenology of late life depression. Copyright © 2017 John Wiley & Sons, Ltd.
authors.affiliation: Division of Geriatric Psychiatry, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, NY, USA.
authors.forename: Patrick J
authors.identifier: 0000-0003-3906-6667
authors.initials: PJ
authors.lastname: Brown
authors.affiliation: Teacher's College, Columbia University, New York, NY, USA.
authors.forename: Dala
authors.initials: D
authors.lastname: Badreddine
authors.affiliation: Division of Geriatric Psychiatry, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, NY, USA.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Roose
authors.affiliation: Division of Geriatric Psychiatry, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, NY, USA.
authors.forename: Bret
authors.initials: B
authors.lastname: Rutherford
authors.affiliation: Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA.
authors.forename: Hilsa N
authors.initials: HN
authors.lastname: Ayonayon
authors.affiliation: Neurology, Psychiatry, Epidemiology and Biostatistics, University of California, San Francisco, CA, USA.
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
authors.affiliation: Intramural Research Program, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA.
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Simonsick
authors.affiliation: Translational Research Institute for Metabolism and Diabetes, Florida Hospital and Sanford Burnham Presbys Medical Discovery Institute, Orlando, FL, USA.
authors.forename: Bret
authors.initials: B
authors.lastname: Goodpaster
authors.affiliation: Translational Research Institute for Metabolism and Diabetes, Florida Hospital and Sanford Burnham Presbys Medical Discovery Institute, Orlando, FL, USA.
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology* / Q000523:psychology*; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000503:physiopathology*; D005221:Fatigue; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D016016:Proportional Hazards Models; D012307:Risk Factors
keywords: depression; fatigability; frailty; later life