Abstract 10606: More Frequent Self-Testing of Prothrombin Time Results in Improved Time in Target Range

BACKGROUND: Anticoagulation (AC) is effective in reducing thromboembolic events for individuals with atrial fibrillation (AF) or mechanical heart valve (MHV), but maintaining patients in target range for international normalized ratio (INR) can be difficult. Evidence suggests that increasing INR testing frequency can improve time in target range (TTR), but this can be impractical with in-clinic testing. As part of The Home INR Study, a randomized controlled trial of in-clinic INR testing every 4 weeks vs. weekly home testing, a subset of study sites included home testing twice weekly and once every four weeks. The study tested the hypothesis that more frequent patient-self testing (PST) via home monitoring increases TTR. METHODS: Of 28 study sites, 6 participated in this substudy. After consent, 1029 candidates with AF or MHV were trained and tested for competency using ProTime INR meters; 787 individuals were assessed as competent and, after second consent, were randomized to 4 arms: (1) high quality AC ...