Encyclopedia of Gerontology and Population Aging

Living Edition
| Editors: Danan Gu, Matthew E. Dupre

Biology of Frailty

  • Alice E. Kane
  • Elise S. Bisset
  • Susan E. HowlettEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-69892-2_356-1


With the aging of the population, frailty has become a critically important area of research. Despite this, there is no universally accepted definition of frailty. Frailty is often considered to be an age-associated decline in functional reserve across numerous physiologic systems, which results in an increased vulnerability to external stressors. Thus, frail older individuals can experience adverse outcomes, including death, in response to even minor stressors. Investigation of the molecular and cellular factors that give rise to frailty, known as the “biology of frailty,” is an emerging field. At present the underlying biology of frailty, and the overlap or distinction from the biology of aging itself, is not well understood.


The study of the biology of frailty has been facilitated by the development of various instruments that can be used to quantify the level of frailty in an individual. The frailty phenotype and frailty indexare two different tools that are...

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Alice E. Kane
    • 1
    • 2
  • Elise S. Bisset
    • 3
  • Susan E. Howlett
    • 3
    • 4
    Email author
  1. 1.Department of GeneticsHarvard Medical SchoolBostonUSA
  2. 2.Charles Perkins CentreUniversity of SydneySydneyAustralia
  3. 3.Department of PharmacologyDalhousie UniversityHalifaxCanada
  4. 4.Department of Medicine (Geriatric Medicine)Dalhousie UniversityHalifaxCanada

Section editors and affiliations

  • Olga Theou
    • 1
  1. 1.Department of MedicineDalhousie UniversityHalifaxCanada