Anticoagulation in the Very Old.

Abstract

One of the most fraught choices clinicians make is deciding whicholderpatients shouldreceiveanticoagulant therapy.Risk of thrombosis and bleeding both increasewith age, and these risks must be balanced with the burdens of anticoagulant monitoring, cost, adherence, and polypharmacy.1 Studies evaluating the net benefit of anticoagulation therapy oftenexclude theoldest andsickestpatients.Consequently,physicians caring for older adults with complex medical conditions instead must rely on extrapolated data and clinical experience; surveys show that patient age acts as a significantdeterrent to theuseof anticoagulation regardless of other risk factors.2 In this issue of JAMA Internal Medicine, Kooistra et al3 offer insight on the risk of bleeding and thrombosis in this understudied age group. They included all patients 90 years or older who were prescribed vitamin K antagonists at an anticoagulation clinic in theNetherlands andmatched themwith equal numbers of patients aged 80 to 89 years and 70 to 79 years based on treatment duration. Compared with patients aged 70 to 79 years, those aged 80 to 89 years had a similar riskofbleeding,whereaspatients90yearsorolderhadamildly increased riskofbleeding.Conversely,patients in their80sand 90s had a markedly higher risk of thrombosis than did patients in their 70s. This study included all patients in the region that clinicians chose to treat with anticoagulation therapy and had no exclusion criteria; thus, it offers valuable informationon realworldoutcomes. Investigatorsshouldusethese inclusivemethods in future studies of the very old. These data also suggest that clinicians are successfully identifying very old patients whocanbegivenanticoagulation therapywith relative safety. However, we still know little about the patients who clinicians chose not to treat with anticoagulation therapy. Beyondabsolute age, frailty,mobility problems, fall risk, anddementia influencedecisions regardinganticoagulation therapy, andwe need data on how these factorsmediate risk of bleedingandthrombosis.Weneedmorestudies that includethevery old and thatmeasure the risk factors that are particularly relevant in the frail older population. The specter of iatrogenic hemorrhage and preventable thrombosis looms large when discussing anticoagulation at any age. Patients and clinicians will benefit greatly from robust and generalizable data when considering these nuanced decisions.