title: The frailty index in Europeans: association with age and mortality.
abstract: BACKGROUND
  the frailty index (FI) is an approach to the operationalisation of frailty based on accumulation of deficits. It has been less studied in Europeans.
  
  
  OBJECTIVE
  to construct sex-specific FIs from a large sample of Europeans and study their associations with age and mortality.
  
  
  METHODS
  longitudinal population-based survey.
  
  
  METHODS
  the Survey of Health, Ageing and Retirement in Europe (SHARE, http://share-dev.mpisoc.mpg.de/).
  
  
  METHODS
  a total of 16,217 females and 13,688 males aged ≥50 from wave 1 (2004-05). Mortality data were collected between 2005 and 2006 (mean follow-up: 2.4 years).
  
  
  METHODS
  regression curve estimations between age and an FI constructed as per the standard procedure. Logistic regressions were used to assess the relative effects of age and the FI towards mortality.
  
  
  RESULTS
  in both sexes, there was a significant non-linear association between age and the FI (females: quadratic R(2) = 0.20, P < 0.001; males: quadratic R(2) = 0.14, P < 0.001). Overall, the FI was a much stronger predictor of mortality than age, even after adjusting for the latter (females: age-adjusted OR 100.5, 95% confidence interval (CI): 46.3-218.2, P < 0.001; males: age-adjusted OR 221.1, 95% CI: 106.7-458.4, P < 0.001).
  
  
  CONCLUSIONS
  the FI had the expected properties in this large sample of Europeans.
authors.affiliation: Department of Medical Gerontology, Trinity College Dublin, Dublin, Ireland. romeror@tcd.ie
authors.forename: Roman
authors.initials: R
authors.lastname: Romero-Ortuno
authors.forename: Rose Anne
authors.initials: RA
authors.lastname: Kenny
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D016330:Frail Elderly / Q000706:statistics & numerical data*; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009026:Mortality; D012044:Regression Analysis; D012737:Sex Factors