title: Quality of life in older age: evidence from an Irish cohort study.
abstract: OBJECTIVE
  To compare the role of different life domains in determining quality of life (QoL) in Ireland with international results.
  
  
  METHODS
  Cross-sectional study of responses to The Irish Longitudinal Study of Ageing.
  
  
  METHODS
  Individuals aged 50 and older living in private residential addresses in the Republic of Ireland.
  
  
  METHODS
  Eight thousand five hundred four individuals living in 6,279 households in the Republic of Ireland (response rate 62%) were interviewed and completed a self-completion questionnaire.
  
  
  METHODS
  Quality of life was measured using the Control, Autonomy, Self-realization and Pleasure measure (CASP-19). The domains of physical and mental health, social participation, economic resources, and sociodemographic status were measured using a large number of indicators. Ordinary least squares regression models were used to estimate the effect of factors on CASP-19, with the relative contribution of different domains to total explanation measured using a measure of statistical fit.
  
  
  RESULTS
  The mean CASP-19 score for the sample was 43.8 (95% confidence interval = 43.6-44.1), significantly higher than the mean score for the English Longitudinal Study of Ageing (mean 42.5: 42.3-42.7). In unadjusted analyses, CASP-19 was curvilinear with age, peaking at 67 and falling thereafter. Controlling for predictors of QoL, CASP-19 continued to rise, at a decreasing rate, with age. Mental health independently explained the largest proportion of variance in CASP-19 (7.6%), but no single domain of life dominated in terms of explanation.
  
  
  CONCLUSIONS
  Increasing longevity can be associated with increasing QoL as long as it is accompanied by reasonable levels of mental and physical health, high-quality relationships, and social participation. Even if physical health becomes poor, evidence suggests that QoL can often remain high as individuals find value and enjoyment in other dimensions of life.
authors.affiliation: Economic and Social Research Institute, Dublin, Ireland. Richard.layte@esri.ie
authors.forename: Richard
authors.initials: R
authors.lastname: Layte
authors.forename: Eithne
authors.initials: E
authors.lastname: Sexton
authors.forename: George
authors.initials: G
authors.lastname: Savva
mesh_terms: D000368:Aged; D000375:Aging / Q000208:ethnology / Q000523:psychology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D015577:Geriatric Assessment; D054624:Health Status Disparities; D006801:Humans; D057187:Independent Living / Q000523:psychology / Q000706:statistics & numerical data; D007494:Ireland / Q000453:epidemiology; D008019:Life Style / Q000208:ethnology*; D016015:Logistic Models; D008297:Male; D008603:Mental Health / Q000706:statistics & numerical data*; D008875:Middle Aged; D011788:Quality of Life; D012944:Social Support; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D026712:Value of Life