title: Longitudinal HRQoL shows divergent trends and identifies constant decliners in asthma and COPD.
abstract: OBJECTIVE
  Monitoring of lung function alone does not adequately identify the high-risk patients among elderly asthma and COPD cohorts. The additional value of Health-Related Quality of Life (HRQoL) development in the detection of patients with a disabling disease in clinical practice is unclear. The aim of this study was to statistically examine the individual development of HRQoL measured using respiratory-specific AQ20 and generic 15D questionnaires.
  
  
  METHODS
  The HRQoL of COPD (N = 739) and asthma (N = 1329) patients was evaluated at 0, 1, 2, and 4 years after recruitment. To determine a five-year HRQoL change for each patient we used mixed-effects modelling for linear trend.
  
  
  RESULTS
  In COPD, the majority (60-80%) of the individuals showed declining trend, whereas in asthma, the majority (46-71%) showed no attenuation in HRQoL. The proportion of constant decliners was estimated higher with the 15D both in asthma (6.3%) and COPD (6.3%) than with AQ20 (3.5 and 4.5%, respectively). The first measurement of HRQoL was found to predict future development of HRQoL. In asthma, obesity-related diseases such as hypertension, diabetes and gastro-esophageal reflux disease best explained the decline, whereas in COPD, age and the level of bronchial obstruction were the main determinants.
  
  
  CONCLUSIONS
  Based on the five-year follow-up, the HRQoL trends significantly diverging from each other could be identified both among the asthma and COPD patients. Compared to cross-sectional HRQoL, the HRQoL trend over a clinically relevant period of time allows us to ignore, to a great extent, the random error of self-assessed HRQoL and thus, it may offer a more accurate measure to describe the disease process.
authors.affiliation: Clinical Research Unit for Pulmonary Diseases and Division of Pulmonology, Helsinki University Central Hospital, Finland. Electronic address: jukka.koskela@helsinki.fi.
authors.forename: J
authors.initials: J
authors.lastname: Koskela
authors.affiliation: Clinical Research Unit for Pulmonary Diseases and Division of Pulmonology, Helsinki University Central Hospital, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Kupiainen
authors.affiliation: Division of Medicine, Dept. of Pulmonary Diseases and Clinical Allergology, Turku University Hospital and University of Turku, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Kilpeläinen
authors.affiliation: Clinical Research Unit for Pulmonary Diseases and Division of Pulmonology, Helsinki University Central Hospital, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Lindqvist
authors.affiliation: Department of Public Health, University of Helsinki, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Sintonen
authors.affiliation: Department of Public Health, University of Helsinki, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Pitkäniemi
authors.affiliation: Division of Medicine, Dept. of Pulmonary Diseases and Clinical Allergology, Turku University Hospital and University of Turku, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Laitinen
mesh_terms: D000368:Aged; D001249:Asthma / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D011788:Quality of Life; D011795:Surveys and Questionnaires
keywords: Asthma; COPD; Decliner; HRQoL; Longitudinal