Investigating Age Appropriate Coagulation Reference Intervals to Support Patient Blood Management in the Elderly: A Verification Study

Ann Clin Lab Sci. 2020 Jul;50(4):545-550.

Abstract

Reference intervals are vital for interpreting coagulation results. Current interval ranges have no upper age limit, although there is evidence that coagulation function changes with age. This study compared coagulation results from healthy people aged >60 years against adult reference intervals for routine clotting assays and thromboelastography (TEG) to determine if reference intervals are relevant to older adults.Samples from healthy blood donors aged >60 years (n=30 male, n=30 female) were tested by TEG® 6s, prothrombin time (PT), activated partial thromboplastin time (aPTT), and derived fibrinogen.All older donor-derived fibrinogen results were within the adult reference intervals, however levels were significantly higher in females. A proportion of TEG® 6s and aPTT results were not within the reference intervals. As populations around the world live longer, these findings question whether older adults require age specific coagulation reference intervals.

Keywords: Coagulation tests; activated partial thromboplastin time; elderly; prothrombin time; reference intervals; thromboelastography.

Publication types

  • Validation Study

MeSH terms

  • Aged
  • Aged, 80 and over
  • Australia
  • Blood Coagulation
  • Blood Coagulation Factors / analysis*
  • Blood Coagulation Factors / standards*
  • Blood Coagulation Tests / methods*
  • Blood Transfusion
  • Female
  • Fibrinogen / metabolism
  • Humans
  • Male
  • Middle Aged
  • Partial Thromboplastin Time
  • Prothrombin Time / methods
  • Reference Values
  • Thrombelastography / methods

Substances

  • Blood Coagulation Factors
  • Fibrinogen