(P-386) Association Between Primary Care Provider Payment Models and Adherence to Anticoagulation in a Sample of Patients with Atrial Fibrillation

Background: Oral anticoagulation (OAC) is recommended in the prevention of stroke among atrial fibrillation (AF) patients. However, only 50–60% of US patients are treated with OAC, and less than half of them adhere to OAC therapy over time.

Objectives: The objective of this study was to compare adherence to OAC between AF patients who received primary care from practices involved in shared-savings (SS) models and patients who received care from practices not involved in SS. Because OAC can save down-stream medical costs associated with averted stroke events, we hypothesized that OAC adherence would be higher among patients receiving care from practices involved in SS.

Methods: Using 2014-2019 claims data from a health insurer in Western Pennsylvania, we identified 24,390 patients diagnosed with AF in 2015-2018 and extracted prescriptions filled for OAC in the 12 months after AF diagnosis. Patients were followed from the date of the first AF diagnosis for 12 months or until disenrollment. We categorized patients according to the payment model of the practice they received primary care from: SS (n=10,352) and non-SS (n=14,038). We constructed logistic regression models to assess the association between involvement in SS and adherence to OAC, while controlling for demographics, clinical characteristics, and index year. OAC adherence was defined as having at least 80% of the follow-up period covered with OAC. Secondary outcomes included adherence to direct oral anticoagulants (DOAC) and adherence to warfarin.

Results: OAC adherence was similar in both groups (38.1% for SS; 37.2% for non-SS), p-value=0.2. After adjustment, adherence to OAC did not statistically differ between SS and non-SS [adjusted odds ratio(aOR): 1.04, 95% CI: 0.98-1.11]. Adherent use of warfarin (aOR:1.08 95%CI: 0.98-1.19) and adherent use of DOAC (aOR:1.01 95% CI 0.94-1.08) did not significantly differ between two groups either. However, the odds of adherent OAC use increased over time: the OR of adherence to OAC was 1.34 95%CI 1.21-1.48 for index year 2016, 1.69 95%CI 1.53-1.87 for index year 2017, and 2.01 95%CI 1.81-2.23 for 2018, all compared to 2015.

Conclusions: Receipt of primary care from a practice involved in SS was not associated with a change in adherence to OAC. However, adherence to OAC improved over time for both treatment groups. Our research demonstrates that the prescribing patterns of anticoagulants with cost-saving potential were not necessarily impacted by enrollment in Shared-savings. Further research is needed to assess whether other alternative physician payment models could promote the adherence of OAC.