Recently accepted paper by COAH trainee and faculty: Perceived Fatigability, Fatigue, and Mortalility in Mid-to-Late Life in the Baltimore Longitudinal Study of Aging

COAH Core Faculty Amal A. Wanigatunga, PhD, MPH, (Assistant Professor of Epidemiology, Aging Track with the Bloomberg School of Public Health (BSPH)) teamed up with fourth-year PhD candidate and COAH trainee Francesca R. Marino, BS, to study Perceived Fatigability, Fatigue, and Mortality in Mid-to-Late Life using data from the Baltimore Longitudinal Study of Aging; their paper on this topic was recently accepted by Medicine & Science in Sports & Exercise and published online ahead of print here.

The premise of the study was developed by Drs. Jennifer Schrack (COAH director), Eleanor Simonsick, and Amal Wanigatunga. Ms. Francesca Marino contributed to the analysis through data management, code review, and conducting sensitivity analyses. Also, Ms. Marino led the writing of the manuscript together with Dr. Wanigatunga, who was the senior author of this paper.

We are pleased to share with you this interview about their findings.

Tony Teano: What prompted you to raise the question studied?

Dr. Wanigatunga: Fatigue is a common complaint among older adults and has been shown to predict elevated risk of mortality. However, fatigue is subjective and usually due to disease and disability. When fatigue is anchored to a physical task, we measure fatigability which gives us an idea of how fast an individual gets fatigued. This combination of the subjective nature of fatigue in response to a physical task has been shown to be predictive of adverse health ranging from cognitive decline to physical impairment, and importantly, among people who appear healthy. Yet its relationship with mortality is relatively unexplored. We wanted to know if fatigability might be more predictive of mortality than fatigue.

Tony Teano: Why did the topic warrant research?

Dr. Wanigatunga: Understanding whether perceived fatigability is more strongly related to mortality risk than self-reported fatigue symptoms among seemingly healthy adults has important implications for prevention and clinical practice. Feelings of fatigue can be avoided through “self-pacing” (e.g., reducing one’s pace of walking in response to fatigue). Measuring fatigability circumvents “self-pacing” by combining feelings of fatigue with a standardized physical task. Fatigability could potentially capture unnoticed but important biological and physiological changes. Findings from this research could help transform how wellness visits are conducted among seemingly healthy individuals and improve development of interventions that aim to combat fatigue.

Tony Teano: Regarding the study’s design and methods, describe the study population and setting.

Francesca Marino: The study population for this research was well-functioning adults aged ≥ 50 years in the Baltimore Longitudinal Study of Aging (BLSA) with usual gait speed > 0.67 meters/second and no self-reported difficulty walking one-quarter mile. Data on perceived fatigability and fatigue were collected at in-person BLSA study visits, where fatigue symptoms were self-reported during an interviewer-assisted interview and perceived fatigability was measured after a 5-minute treadmill walk at 0.67 meters/second at 0% grade.

Tony Teano: What did you discover from your investigation?

Francesca Marino: We found that higher perceived fatigability and self-reported fatigue symptoms were similarly associated with higher risk of all-cause mortality. However, these associations differed by history of certain chronic conditions. We found that perceived fatigability was related to mortality risk among seemingly healthy participants without arthritis, whereas unusual tiredness was related to mortality risk among those with diabetes or pulmonary disease.

Tony Teano: What is the single most important takeaway from your findings?

Francesca Marino: These findings suggest that perceived fatigability assessments might be useful for health screening and long-term mortality risk assessment for well-functioning adults, while asking about unusual tiredness appears to be more disease-specific regarding mortality risk.

Tony Teano: Tell us about the clinical or public health implications of the study. How would a solution to this problem improve the wellbeing of older adults and/or clinical care?

Francesca Marino: If our findings are true, implementing targeted evaluation of perceived fatigability and unusual tiredness into preventative efforts and clinical practice could potentially help identify patients at higher risk of mortality. This might then help improve the health and longevity of these patients if the causes of fatigability or unusual tiredness are intervenable. More research is needed to understand the unique reasons that increase perceived fatigability and tiredness and possibly drive this increased mortality risk, though.

Tony Teano: About next steps–what unanswered or new questions remain to be investigated?

Francesca Marino: An important unanswered question is to understand the mechanism of how increased perceived fatigability is related to mortality risk among healthy middle aged and older adults. This could then potentially inform interventions to attenuate mortality risk by acting on these mechanisms. Another new question is to determine the best way to evaluate perceived fatigability in preventive care and clinical settings. The current study used a standardized treadmill test, but future work could explore measuring fatigability in the free-living environment. One potential method could be through the use of accelerometry data.

Many thanks to Dr. Wanigatunga and Ms. Francesca Marino for taking the time to tell us about this exciting new research and its implications.

Other related papers of interest conducted by their group include: 

  • Gresham G, Dy SM, Zipunnikov V, Browner IS, Studenski SA, Simonsick EM, et al. Fatigability and endurance performance in cancer survivors: Analyses from the Baltimore Longitudinal Study of Aging. Cancer. 2018 Mar 15;124(6):1279–87. 
  • Salerno EA, Wanigatunga AA, An Y, Urbanek JK, Simonsick EM, Ferrucci L, et al. Longitudinal Association Between Perceived Fatigability and Cognitive Function in Older Adults: Results from the Baltimore Longitudinal Study of Aging. Newman A, editor. The Journals of Gerontology: Series A. 2020 Sep 16;75(9):e67–73. 
  • Schrack JA, Simonsick EM, Glynn NW. Fatigability: A Prognostic Indicator of Phenotypic Aging. The Journals of Gerontology: Series A. 2020 Sep 16;75(9):e63–6. 
  • Schrack JA, Wanigatunga AA, Zipunnikov V, Kuo PL, Simonsick EM, Ferrucci L. Longitudinal Association Between Energy Regulation and Fatigability in Mid-to-Late Life. Newman A, editor. The Journals of Gerontology: Series A. 2020 Sep 16;75(9):e74–80. 
  • Simonsick EM, Schrack JA, Glynn NW, Ferrucci L. Assessing Fatigability in Mobility-Intact Older Adults. J Am Geriatr Soc. 2014 Feb;62(2):347–51. 
  • Simonsick EM, Glynn NW, Jerome GJ, Shardell M, Schrack JA, Ferrucci L. Fatigued, but Not Frail: Perceived Fatigability as a Marker of Impending Decline in Mobility-Intact Older Adults. J Am Geriatr Soc. 2016;64(6):1287–92. 
  • Qiao Y, Martinez‐Amezcua P, Wanigatunga AA, Urbanek JK, Simonsick EM, Ferrucci L, et al. Association Between Cardiovascular Risk and Perceived Fatigability in Mid‐to‐Late Life. J Am Heart Assoc. 2019 Aug 20;8(16). 
  • Wanigatunga AA, Simonsick EM, Zipunnikov V, Spira AP, Studenski S, Ferrucci L, et al. Perceived Fatigability and Objective Physical Activity in Mid- to Late-Life. The Journals of Gerontology: Series A. 2018 Apr 17;73(5):630–5. 

On X (Twitter), You may follow Dr. Amal Wanigatunga @AmalForResearch, and Ms. Francesca Marino @marinofran_.

By Anthony L. Teano, MLA
Communications Specialist