Functional correlates of self-reported energy levels in the Health, Aging and Body Composition Study

Abstract

Background Effects of fatigue on health in older age are well studied, yet little is known about the clinical relevance of energy perception. Aims To explore cross-sectional associations of self-reported energy with physical and mental health metrics in the Health, Aging, and Body Composition Study. Methods Participants rated their energy from 0 to 10; the outcome was energy dichotomized at the median (≥ 7 = higher energy). Four domains were assessed: depressive symptoms (Center for Epidemiologic Studies Depression Scale); physical performance (function: usual and rapid gait speed; fitness: 400-m walk time); physical activity (casual walking, walking for exercise, and intense exercise); and cognitive function (Modified Mini-Mental State Examination and Digit Symbol Substitution Test). Covariates bivariately associated with energy entered a multivariable logistic regression model, adjusted for demographics, chronic conditions, and strength. Results Depressive symptoms, physical performance and activity, but not cognition, were bivariately associated with energy (p < 0.0005). Younger age, male sex, greater strength, and absence of chronic conditions predicted higher energy (p < 0.001). In a multivariable model, depressive symptoms [adjusted odds ratio (aOR) 95% CI 0.69 (0.62, 0.76)] and 400-m walk times [aOR = 0.81 (0.72, 0.91)] were inversely associated with energy; usual and rapid gait speed [aOR = 1.3 (1.2, 1.4); aOR = 1.2 (1.1–1.4)], and time spent in intense exercise [aOR = 1.4 (1.1–1.7)] were positively associated with energy. Discussion In this cohort with a range of chronic conditions and fatigue, perceiving higher energy levels may reflect better emotional and physical health. Conclusion Energy should be considered in multidimensional clinical assessments of older age.

Declining energy predicts incident mobility disability and mortality risk in healthy older adults

“…Associations were robust to baseline SEL, demographic and health covariates, as well as self-reported tiredness, and volitional energy-related behaviors such as physical activity, appetite, or sleep. Our findings lend credence to the notion that SEL may be an early indicator of suboptimal aging 8,[25][26][27] and are the first to identify that SEL decline is associated with prospective clinically-relevant health outcomes. The current study further highlights the value of subjective perceptions to predict clinically-relevant outcomes.…”

“…The analytic sample of 2021 older adults had an average baseline age of 74.5 years ( SD = 2.8); a majority of the sample was white ( n = 1320, 65.3%), and there were slightly more women ( n = 1014, 50.2%) (Table 1). The sample reported having generally high baseline energy (average of 6.9 out of 10, corresponding to high energy) similar to that in other Health ABC studies 8,25 . Of the 2021 participants, 947 (46.9%) developed mobility disability and 348 (17.2%) died over the study period.…”

“…Our findings lend credence to the notion that SEL may be an early indicator of suboptimal aging 8,25–27 and are the first to identify that SEL decline is associated with prospective clinically‐relevant health outcomes. The current study further highlights the value of subjective perceptions to predict clinically‐relevant outcomes 8,25,27 …”

“…The current study further highlights the value of subjective perceptions to predict clinically-relevant outcomes. 8,25,27 Why would SEL decline predict physical disability? One way to answer this question is to examine the factors contributing to both SEL decline and disability, and then assess whether such factors explain the SEL-related effects on disability.…”

“…While prior literature treated reduced energy as synonymous with increased fatigue or tiredness, newer research suggests that energy and fatigue are distinct unipolar states rather than each other's inverse. [5][6][7] Recent cross-sectional work from our research group 8 indicates that there is a weak association between self-reported fatigue (binary tiredness over prior month) and energy. Moreover, energy and fatigue have distinct neurobiological substrates.…”