Abstract 237: Anticoagulant Use For the Prevention of Stroke in Patients with Atrial Fibrillation: Findings From a Multi-Payer Analysis

Abstract

Background: Oral anticoagulation is recommended by the American College of Chest Physicians for stroke prevention in intermediate/high stroke risk atrial fibrillation (AF) patients. This study analyzed recent pharmacy and medical claims from Medicaid, Medicare and commercial insurance databases to estimate the risk of stroke, occurrence of stroke hospitalization, and the use of treatment guideline-recommended anticoagulants among patients with AF. Methods: Retrospective data analyses were performed using the Anticoagulant Quality Improvement Analyzer, a software tool designed to analyze health plan data to evaluate stroke risk and identify gaps in care in specific populations with AF. Four data sources were analyzed: 1) IMS LifeLink Database (IMS)- includes commercially insured claims; 2) MarketScan Commercial Database (MarketScanComm)- includes commercially insured claims; 3) MarketScan Medicare Supplemental Database (MarketScanMedicare)- includes employer-sponsored Medicare Supplemental plans only; and 4) Florida Medicaid Database (Medicaid). Included patients were ≥ 18 years old with a new or existing diagnosis of AF. The first observed AF diagnosis constituted the index date, with patient outcomes assessed over a maximum of two years. Study measures included stroke risk (as identified by CHADS2 Score), inpatient stroke hospitalization, and anticoagulant use (stratified by stroke risk and hospitalization). Results: Total samples (mean age) included 25,710 (71.6) from IMS, 21,976 (56.2) from MarketScanComm, 38,643 (79.7) from MarketScanMedicare, and 4,901 (66.8) from Medicaid. High stroke risk (CHADS2 ≥2 points) was estimated in 54% (IMS), 22% (MarketScanComm), 64% (MarketscanMedicare), and 62% (Medicaid) of the total eligible population. Overall, 35%, 29%, 38%, and 16% of all AF patients received an anticoagulant medication in IMS, MarketScanComm, MarketScanMedicare, and Medicaid, respectively. Among patients at high risk for stroke, 39% (5,414/13,955; IMS), 39% (1,934/4,935; MarketScanComm), 40% (9,822/24,776; MarketScanMedicare), and 19% (566/3,015; Medicaid) received any anticoagulant. Rates of stroke hospitalization ranged from 1 - 2% across databases. Of patients hospitalized for stroke, 28% (173/616; IMS), 37% (54/146; MarketScanComm), 37% (341/912; MarketScanMedicare) and 50% (20/40; Medicaid) were treated with an anticoagulant in the outpatient setting. Conclusions: Many AF patients in selected commercial, Medicare-eligible, and Medicaid populations, including those at high risk of stroke, do not receive appropriate thromboprophylaxis, as recommended by treatment guidelines. Increased use of the analyzer and similar software may support enhanced education efforts aimed at improving adherence to guidelines and quality of care.