PERCEIVED AND PERFORMANCE FATIGABILITY: NOVEL FINDINGS ON CORRELATES, CONSEQUENCES, AND CANDIDATE GENES

Abstract

Abstract Characterizing fatigability enables quantification of an individual’s susceptibility to fatigue in the context of standardized physical task(s). This approach eliminates self-pacing, and is a less-biased, more sensitive approach to assess the presence and severity of fatigue, a critical prodromal symptom of chronic and acute health conditions. Collectively, we have established the Pittsburgh Fatigability Scale (PFS) and Borg Rating of Perceived Exertion at the end of a standardized 5-minute treadmill walk (RPE Fatigability) as prognostic indicators of aging-related outcomes. Recently, we extended our methodological work in developing a novel accelerometry-based performance fatigability measure of slowing down during in-lab walking (Pittsburgh Performance Fatigability Index, PPFI). This symposium presents findings from the Study of Muscle, Mobility, and Aging (SOMMA), Long Life Family Study (LLFS), and Baltimore Longitudinal Study of Aging (BLSA). Specifically, using SOMMA, Ms. Qiao will share development and validation of the PPFI using a usual-paced 400m walk, Ms. Moffit will report the association of fitness (i.e., VO2peak) with PFS physical and mental fatigability, and extending the SOMMA findings, Dr. Moored will detail the dual roles of fitness and fatigability on life-space mobility. Using LLFS data, Ms. Gay will report associations of variants (SNPs) in 272 candidate autosomal genes involved in energy metabolism (previously associated with mitochondrial dysfunction disease) with PFS physical fatigability. Lastly, using BLSA data, Dr. Wanigatunga will compare the discriminatory power of RPE Fatigability versus general fatigue symptoms for predicting mortality. Our Discussant, Dr. Simonsick, will provide critical review in the context of new directions for fatigability research.