Predictors of self-reported adherence to direct oral anticoagulation in a population of elderly men and women with non-valvular atrial fibrillation

There is a general lack of studies evaluating medication adherence with self-report scales for elderly patients in treatment with direct oral anticoagulants (DOACs). The aim of the study was to assess the degree of adherence to DOAC therapy in a population of elderly outpatients aged 65 years or older affected by non-valvular atrial fibrillation (NVAF), using the 4-item Morisky Medication Adherence Scale, and to identify potential factors, including the geriatric multidimensional evaluation, which can affect adherence in the study population. A total of 103 subjects, anticoagulated with DOACs for NVAF in primary or secondary prevention, were eligible; 76 showed adequate adhesion to anticoagulant therapy, while 27 showed inadequate adherence. Participants underwent biochemical assessment and Morisky Scale, Instrumental Activities of Daily Living, CHA2DS2-VASc, HAS-BLED, mental status and nutritional evaluations were performed. 2% of subjects assumed Dabigatran at low dose, while 7.8% at standard dose, 9.7% assumed low-dose of Rivaroxaban and 30.1% at standard dose, 6.8% assumed Apixaban at low dose and 39.7% at standard dose, and finally 1% assumed Edoxaban at low dose and 2.9% at standard dose. Most subjects took the DOACs without help (80.6%), while 16 subjects were helped by a family member (15.5%) and 4 were assisted by a caregiver (3.9%). Binary logistic regression considered inappropriate adherence as a dependent variable, while age, male sex, polypharmacotherapy, cognitive decay, caregiver help for therapy assumption, duration of DOAC therapy and double daily administration were considered as independent variables. The double daily administration was an independent factor, determining inappropriate adherence with an OR of 2.88 (p = 0.048, CI 1.003-8.286).