title: Impact of nine chronic conditions for US adults aged 65 years and older: an application of a hybrid estimator of quality-adjusted life years throughout remainder of lifetime.
abstract: To estimate quality-adjusted life years (QALY) loss due to each of the following nine chronic conditions-depression, diabetes mellitus, hypertension, heart disease, stroke, emphysema, asthma, arthritis, and cancer.
  
  
  
  We ascertained respondents' health-related quality of life scores and mortality status from the 2005 to 2008 National Health and Nutrition Examination Survey (NHANES) with mortality follow-up data through December 31, 2011. We included respondents aged 65 years and older (n = 2380). A hybrid estimator was used to calculate QALY from two parts: QALY during the follow-up period and QALY beyond the follow-up period. We calculated QALY by each of the nine chronic conditions.
  
  
  
  For persons aged 65 and older, QALY throughout the reminder of lifetime was 12.3 years. After adjusting for age- and sex-related differences, depression had an associated 8.2 years of QALY loss; diabetes, 5.6 years; hypertension, 2.5 years; heart disease, 5.4 years; stroke, 6.4 years; emphysema, 8.0 years; asthma, 4.8 years; arthritis, 0.3 years; and cancer, 2.5 years. Compared to persons without any chronic conditions, persons with one condition had an associated 4.7 years of QALY loss; persons with two conditions, 7.9 years; and persons with three or more conditions, 10.8 years.
  
  
  
  This study presents a QALY estimator for respondents in the NHANES-Linked Mortality File and demonstrates the utility of this method to other follow-up data. Continued application of our method would enable the burden of disease to be compared for a range of health conditions and risk factors in the ongoing effort to improve population health.
authors.affiliation: Department of Biostatistics, Mailman School of Public Health and School of Nursing, Columbia University, 617 West 168th Street, New York, NY, 10032, USA. hj2198@columbia.edu.
authors.forename: Haomiao
authors.initials: H
authors.lastname: Jia
authors.affiliation: Department of Community Health and Social Medicine, Sophie Davis School of Biomedical Education/CUNY Medical School, New York, NY, 10031, USA.
authors.forename: Erica I
authors.initials: EI
authors.lastname: Lubetkin
mesh_terms: D000368:Aged; D002908:Chronic Disease / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D019057:Quality-Adjusted Life Years; D018434:Sickness Impact Profile; D014481:United States
keywords: Burden of disease; Chronic conditions; Health-related quality of life (HRQOL); Quality-adjusted life year (QALY)