Po-04-216 patient enabled inr optimization : a multicenter prospective study

For patients using Vitamin K antagonists (VKA), maximizing time within the therapeutic range (TTR) reduces stroke, major hemorrhage, and death. Despite improvements in counselling and patient education, patients using Vitamin K antagonists have a poor TTR. The objective of this study was to evaluate the effectiveness and safety of a smartphone application for improvement in TTR with minimal physician interference. Content was customized on a smartphone based platform (INR Assist) for patients using VKA which included automated INR dosage adjustment, tracking, reminders, and education. A multicenter prospective open-label study was conducted at two tertiary care medical centers with patients using VKA for at least the previous 6 months. In order to tailor INR dose adjustment, patients were enrolled into either normal bleeding/thrombotic risk (Group A), high bleeding risk (Group B) or high thrombotic risk (Group C) at the discretion of the treating physician. The primary endpoint of the study was the change in TTR before and after 6 months of using INR Assist. Secondary endpoints included stroke, major bleeding, and red-alerts (INR not in TTR for 3 consecutive entries, INR>6.0, INR<1.5) by the application that required direct physician assistance. There were 184 patients (mean age 50.5 + 8.2, males 68.5%) using VKA for either AF stroke prevention (54.9%), metallic valve replacement (38.6%), or venous thromboembolism (6.5%) were included in the study between January 2019 and June 2022. The number of patients enrolled in Groups A, B, and C were 145 (90.2%), 10 (6.0%), and 7 (3.8%), respectively. After a minimum of 6 months of using INR Assist, TTR improved from 59.2 + 6.7% to 80.5 + 9.4% (p<0.001). The improvement in TTR was similar in all three groups (p<0.001). There were fewer bleeding(3.1% vs. 1.2%, p=0.105) and thrombotic events (2.5% vs. 0.6%, p=0.115) following utilization of INR Assist. Overall there were 27 red-alerts during the study period. These alerts included INRs not within therapeutic range for 3 consecutive entries (n=9, 33.3%), INR > 6.0 (n=11, 40.7%), and INR < 1.5 (n=7, 25.9%). Smart phone based mobile application (INR Assist) by patients using VKAs was safe and led to an improvement in TTR.