Background:
Recent research has shown strong provider-level variation in oral anticoagulation (OAC) use in atrial fibrillation (AF). The objective of the present study was to examine predictors of prescribing OAC to newly diagnosed AF patients, with special attention to prescribing low-dose direct oral anticoagulant agents (DOACs) to patients with no diagnosis of chronic kidney disease (CKD).
Methods:
Using 2013-2014 Medicare claims data, we identified patients newly diagnosed with AF who had CHA2DS2-VASc score≥2. Our sample included 19,390 patients who did not initiate OAC, and 22,299 OAC initiators, among whom 12,786 initiated warfarin, 5,984 high-dose DOACs and 3,529 low-dose DOACs. We constructed logistic regression models to estimate the effect of patient demographics, clinical characteristics, provider specialty, and insurance factors on OAC initiation and likelihood of prescribing low dose DOAC in patients with no CKD.
Results:
As shown in the table, age, gender, heart failure, and a history of bleeding affected the initiation of OAC as well as DOAC dosing. White patients were more likely to initiate OAC, but race did not affect DOAC dosing. Use of antiplatelet agents decreased the odds of OAC initiation by 27% (95%CI, 23%-31%), but did not impact DOAC dosing. The odds of OAC initiation decreased by 10% (95%CI, 6%-15%) for each point increase in the Geographic Practice Cost Index for malpractice. The odds of initiating low-dose DOACs were 30% (95%CI, 11%-38%) lower for patients seen by cardiologists than for those seen by internists or family practitioners.
Conclusions:
In addition to demographics and clinical characteristics, provider and insurance factors have a strong impact on initiation and dosing of OAC.
Trajectories of Oral Anticoagulation Adherence Among Medicare Beneficiaries Newly Diagnosed With Atrial Fibrillation
