title: Cross-Sectional and Longitudinal Associations Between Anemia and Frailty in Older Australian Men: The Concord Health and Aging in Men Project.
abstract: BACKGROUND
  Anemia and frailty are both common in older people and are associated with adverse health outcomes. There have been some cross-sectional studies of anemia and frailty but no longitudinal studies. The objectives of this study were to examine cross-sectional and longitudinal associations between anemia and frailty in older Australian men.
  
  
  METHODS
  A total of 1666 men aged 70 years and older from the Concord Health and Aging in Men Project were assessed at baseline (2005-2007), 1314 men came for the 2-year follow-up between 2007 and 2009, and of those, 917 men returned for the 5-year follow-up between 2012 and 2013. The main outcome measurement was frailty, assessed using the Cardiovascular Health Study method. Anemia was defined as a hemoglobin levels <13.0 g/dL. Covariates included age, income, body mass index, measures of health, estimated glomerular filtration rate, and inflammatory markers (white cell count and albumin).
  
  
  RESULTS
  The prevalence of anemia was 14.6% at baseline, 16.2% at 2-year follow-up, and 19.4% at 5-year follow-up. Prevalence of frailty was 9.1% at baseline and 9.7 % at both 2- and 5-year follow-up. Among men aged 70-74 at baseline, prevalence of frailty was 4.5%, but at 5-year follow-up the prevalence was 9.0%. There were significant cross-sectional associations between anemia and frailty in unadjusted [odds ratio, [OR 5.03 (95% confidence interval, CI 3.50, 7.25, P < .0001)] and in fully adjusted analysis [OR 2.90 (95% CI 1.87, 4.51, P < .0001)]. Generalized estimating equations time-lag models were used to examine the longitudinal associations between repeated measurements of hemoglobin and frailty. There were significant associations between measurements of anemia and frailty in unadjusted [OR 2.51 (95% CI 1.58, 4.00, P < .0001] and in fully adjusted analysis (OR 1.80, 95% CI 1.14, 2.85, P = .01).
  
  
  CONCLUSIONS
  Anemia was associated with frailty in both cross-sectional and longitudinal analyses, and anemia precedes frailty in men who were nonfrail at baseline. Low hemoglobin levels among patients may alert clinicians to the increased risk of frailty.
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia; School of Public Health, University of Sydney, Sydney, New South Wales, Australia; The Australian Research Council Center of Excellence in Population Aging Research, University of Sydney, Sydney, New South Wales, Australia. Electronic address: vasant.hirani@sydney.edu.au.
authors.forename: Vasant
authors.initials: V
authors.lastname: Hirani
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Vasi
authors.initials: V
authors.lastname: Naganathan
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Fiona
authors.initials: F
authors.lastname: Blyth
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia; Australian and New Zealand Army Corps (ANZAC) Research Institute and Charles Perkins Center, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: David G
authors.initials: DG
authors.lastname: Le Couteur
authors.affiliation: School of Public Health, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kelly
authors.affiliation: Department of Andrology, Concord Hospital and ANZAC Research Institute, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Handelsman
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Louise M
authors.initials: LM
authors.lastname: Waite
authors.affiliation: Center for Education and Research on Aging, Concord Hospital, University of Sydney, Sydney, New South Wales, Australia; School of Public Health, University of Sydney, Sydney, New South Wales, Australia; The Australian Research Council Center of Excellence in Population Aging Research, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Cumming
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D016021:Epidemiologic Studies; D016330:Frail Elderly / Q000706:statistics & numerical data; D006801:Humans; D008137:Longitudinal Studies; D008297:Male
keywords: Anemia; frailty; older men; population study