title: The impact of frailty on coagulation and responses to warfarin in acute older hospitalised patients with atrial fibrillation: a pilot study.
abstract: BACKGROUND
  The evidence on coagulation changes with frailty is not consistent and clinical studies suggest that frail older people may be at an increased risk of bleeding complications with anticoagulant therapy.
  
  
  OBJECTIVE
  This study aims to assess the impact of frailty on coagulation function and on response to warfarin.
  
  
  METHODS
  Inpatients aged over 65 years with atrial fibrillation (AF) were recruited. Frailty was determined using the Reported Edmonton Frail Scale. The Overall Haemostatic Potential (OHP) and Calibrated Automated Thrombogram (CAT) were used to globally assess coagulation function.
  
  
  RESULTS
  Data of 95 participants were analysed, mean age 85.5 ± 6.2, 40% female, and 50.5% frail. Among participants not on anticoagulants (N = 36), there was an increased fibrin generation and decreased thrombin generation compared to the local established normal ranges in young healthy volunteers; the frail had significantly reduced fibrin generation compared to the non-frail. In the warfarin-treated group (N = 59), there was no difference on coagulation profiles between the frail and the non-frail from any of the coagulation tests.
  
  
  CONCLUSIONS
  In this cohort of acute hospitalised patients with AF, the observed decreased fibrin generation in the frail may reflect decreased acute phase response as suggested with the lower plasma fibrinogen in that group. There was no difference in coagulation profiles between the frail and the non-frail amongst those taking warfarin. Compared to young healthy volunteers, older inpatients had increased fibrin generation and decreased thrombin generation. The findings reflect the complex interaction between age, frailty, acute illness, and coagulation.
authors.affiliation: Departments of Clinical Pharmacology and Aged Care, Royal North Shore Hospital and Kolling Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia. nngu9517@uni.sydney.edu.au.|Sydney School of Public Health, University of Sydney, Sydney, NSW, Australia. nngu9517@uni.sydney.edu.au.
authors.forename: Tu Ngoc
authors.initials: TN
authors.lastname: Nguyen
authors.affiliation: Department of Haematology and Transfusion Medicine, Royal North Shore Hospital and Northern Blood Research Centre, Kolling Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Morel-Kopp
authors.affiliation: Department of Haematology and Transfusion Medicine, Royal North Shore Hospital and Northern Blood Research Centre, Kolling Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.
authors.forename: Dominic
authors.initials: D
authors.lastname: Pepperell
authors.affiliation: Sydney School of Public Health, University of Sydney, Sydney, NSW, Australia.
authors.forename: Robert Graham
authors.initials: RG
authors.lastname: Cumming
authors.affiliation: Departments of Clinical Pharmacology and Aged Care, Royal North Shore Hospital and Kolling Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia. sarah.hilmer@sydney.edu.au.
authors.forename: Sarah Nicole
authors.initials: SN
authors.lastname: Hilmer
authors.affiliation: Department of Haematology and Transfusion Medicine, Royal North Shore Hospital and Northern Blood Research Centre, Kolling Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.
authors.forename: Christopher Morice
authors.initials: CM
authors.lastname: Ward
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000925:Anticoagulants / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy; D001777:Blood Coagulation; D015331:Cohort Studies; D005260:Female; D000073496:Frailty / Q000503:physiopathology*; D006801:Humans; D007297:Inpatients; D008297:Male; D010865:Pilot Projects; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin
keywords: Acute phase response; Anticoagulation; CAT; Frailty; OHP