title: Physiologic frailty as a sign of accelerated aging among adult survivors of childhood cancer: a report from the St Jude Lifetime cohort study.
abstract: OBJECTIVE
  Frailty, a phenotype reported among 9.9% of individuals 65 years old and older (9.6% of women; 5.2% of men), has not been assessed among adult childhood cancer survivors (CCS). We estimated the prevalence of frailty and examined associations with morbidity and mortality.
  
  
  METHODS
  Participants included 1,922 CCS at least 10 years from original cancer diagnosis (men, 50.3%; mean age, 33.6 ± 8.1 years) and a comparison population of 341 participants without cancer histories. Prefrailty and frailty were defined as two and ≥ three of the following conditions: low muscle mass, self-reported exhaustion, low energy expenditure, slow walking speed, and weakness. Morbidity was defined as grade 3 to 4 chronic conditions (Common Terminology Criteria for Adverse Events version 4.0). Fisher's exact tests were used to compare, by frailty status, percentages of those with morbidity. In a subset of 162 CCS who returned for a second visit, Poisson regression was used to evaluate associations between frailty and new onset morbidity. Cox proportional hazards regression was used to evaluate associations between frailty and death.
  
  
  RESULTS
  The prevalence of prefrailty and frailty were 31.5% and 13.1% among women and 12.9% and 2.7% among men, respectively, with prevalence increasing with age. Frail CCS were more likely than nonfrail survivors to have a chronic condition (82.1% v 73.8%). In models adjusted for existing chronic conditions, baseline frailty was associated with risk of death (hazard ratio, 2.6; 95% CI, 1.2 to 6.2) and chronic condition onset (relative risk, 2.2; 95% CI, 1.2 to 4.2).
  
  
  CONCLUSIONS
  The prevalence of frailty among young adult CCS is similar to that among adults 65 years old and older, suggesting accelerated aging.
authors.affiliation: Kirsten K. Ness, Kevin R. Krull, Kendra E. Jones, Daniel A. Mulrooney, Gregory T. Armstrong, Daniel M. Green, Wassim Chemaitilly, Webb A. Smith, Carmen L. Wilson, Kyla Shelton, Deo Kumar Srivastava, Sabeen Ali, Leslie L. Robison, Melissa M. Hudson, St Jude Children's Research Hospital, Memphis, TN; Charles A. Sklar, Memorial Sloan-Kettering Cancer Center, New York, NY.
authors.forename: Kirsten K
authors.initials: KK
authors.lastname: Ness
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Krull
authors.forename: Kendra E
authors.initials: KE
authors.lastname: Jones
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Mulrooney
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Armstrong
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Green
authors.forename: Wassim
authors.initials: W
authors.lastname: Chemaitilly
authors.forename: Webb A
authors.initials: WA
authors.lastname: Smith
authors.forename: Carmen L
authors.initials: CL
authors.lastname: Wilson
authors.forename: Charles A
authors.initials: CA
authors.lastname: Sklar
authors.forename: Kyla
authors.initials: K
authors.lastname: Shelton
authors.forename: Deo Kumar
authors.initials: DK
authors.lastname: Srivastava
authors.forename: Sabeen
authors.initials: S
authors.lastname: Ali
authors.forename: Leslie L
authors.initials: LL
authors.lastname: Robison
authors.forename: Melissa M
authors.initials: MM
authors.lastname: Hudson
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D002648:Child; D002908:Chronic Disease / Q000453:epidemiology; D015331:Cohort Studies; D004734:Energy Metabolism; D005221:Fatigue / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D018908:Muscle Weakness / Q000453:epidemiology*; D009369:Neoplasms; D016012:Poisson Distribution; D015995:Prevalence; D016016:Proportional Hazards Models; D017741:Survivors / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology; D016138:Walking; D055815:Young Adult