PFS study links severe physical fatigability to 2.33-fold mortality risk in older adults
A prospective study of 2,906 older adults found perceived physical fatigability independently predicts mortality over 2.7 years.
Researchers evaluated the prognostic value of perceived physical fatigability as an independent predictor of mortality risk among older adults, publishing their findings in The Journals of Gerontology Series A. The analysis involved 2,906 participants enrolled in the Long Life Family Study, who had a mean age of 73.5 years (standard deviation 10.4), with 54.2% women and 99.7% identifying as white oup.com
The Journals of Gerontology Series Aoup.comOpen source ↗.
Baseline measurements were collected at Visit 2 between 2014 and 2017, followed by an average monitoring period of 2.7 years (standard deviation 1.0). To quantify perceived physical fatigability, investigators administered the Pittsburgh Fatigability Scale (PFS), a validated 10-item self-report questionnaire with overall scores ranging from 0 to 50, where higher values denote greater perceived fatigability.
Mortality Analysis and Risk Ratios
Vital status was tracked through December 31, 2019, utilizing field center reports from relatives, annual telephone check-ins, published obituaries, and Denmark's Civil Registration System. Participants remaining alive were censored at the date of their last confirmed contact. Cox proportional hazard models evaluated mortality against fatigability severity while adjusting for familial relatedness and other covariates.
Overall age-adjusted PFS Physical scores were significantly higher among participants who died, averaging 19.1 (standard error 0.8), compared to 12.2 (standard error 0.4) for surviving individuals (p < .001) oup.com
The Journals of Gerontology Series Aoup.comOpen source ↗. Across age strata, this difference remained statistically significant, except in the group aged 60–69 years. Fully adjusted regression models revealed that individuals exhibiting the most severe fatigability, defined by a PFS score of 25 or higher, were over twice as likely to die (hazard ratio 2.33; 95% confidence interval 1.65–3.28) relative to individuals scoring below 25.
Clinical Value of Perceived Fatigability
The authors concluded that the Pittsburgh Fatigability Scale serves as a noninvasive patient-reported indicator reflecting phenotypic aging. According to the research group, standardized scoring captures both overt and underlying disease burdens that contribute to elevated mortality risks in older populations.
