title: Physical function and self-rated health status as predictors of mortality: results from longitudinal analysis in the ilSIRENTE study.
abstract: BACKGROUND
  Physical function measures have been shown to predict negative health-related events in older persons, including mortality. These markers of functioning may interact with the self-rated health (SRH) in the prediction of events. Aim of the present study is to compare the predictive value for mortality of measures of physical function and SRH status, and test their possible interactions.
  
  
  METHODS
  Data are from 335 older persons aged >or= 80 years (mean age 85.6 years) enrolled in the "Invecchiamento e Longevità nel Sirente" (ilSIRENTE) study. The predictive values for mortality of 4-meter walk test, Short Physical Performance Battery (SPPB), hand grip strength, Activities of Daily Living (ADL) scale, Instrumental ADL (IADL) scale, and a SRH scale were compared using proportional hazard models. Kaplan-Meier survival curves for mortality and Receiver Operating Characteristic (ROC) curve analyses were also computed to estimate the predictive value of the independent variables of interest for mortality (alone and in combination).
  
  
  RESULTS
  During the 24-month follow-up (mean 1.8 years), 71 (21.2%) events occurred in the study sample. All the tested variables were able to significantly predict mortality. No significant interaction was reported between physical function measures and SRH. The SPPB score was the strongest predictor of overall mortality after adjustment for potential confounders (per SD increase; HR 0.64; 95%CI 0.48-0.86). A similar predictive value was showed by the SRH (per SD increase; HR 0.76; 95%CI 0.59-0.97). The chair stand test was the SPPB subtask showing the highest prognostic value.
  
  
  CONCLUSIONS
  All the tested measures are able to predict mortality with different extents, but strongest results were obtained from the SPPB and the SRH. The chair stand test may be as useful as the complete SPPB in estimating the mortality risk.
authors.affiliation: Dipartimento di Scienze Gerontologiche, Geriatriche e Fisiatriche, Università Cattolica del Sacro Cuore, Roma, Italy. macesari@gmail.com
authors.forename: Matteo
authors.initials: M
authors.lastname: Cesari
authors.forename: Graziano
authors.initials: G
authors.lastname: Onder
authors.forename: Valentina
authors.initials: V
authors.lastname: Zamboni
authors.forename: Todd
authors.initials: T
authors.lastname: Manini
authors.forename: Ronald I
authors.initials: RI
authors.lastname: Shorr
authors.forename: Andrea
authors.initials: A
authors.lastname: Russo
authors.forename: Roberto
authors.initials: R
authors.lastname: Bernabei
authors.forename: Marco
authors.initials: M
authors.lastname: Pahor
authors.forename: Francesco
authors.initials: F
authors.lastname: Landi
mesh_terms: D000203:Activities of Daily Living; D000369:Aged, 80 and over; D001294:Attitude to Health; D005260:Female; D015577:Geriatric Assessment; D018737:Hand Strength; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009026:Mortality; D004856:Postural Balance; D012307:Risk Factors; D011795:Surveys and Questionnaires; D016138:Walking