Modeling the impact of real-world adherence to once-daily (QD) versus twice-daily (BID) non-vitamin K antagonist oral anticoagulants on stroke and major bleeding events among non-valvular atrial fibrillation patients
Current Medical Research and Opinion, 2019
Objectives
To estimate the real-world (RW) impact of adherence to once-daily (QD: rivaroxaban and edoxaban) and twice-daily (BID: apixaban and dabigatran) non-vitamin K antagonist (NOACs) on the risk of stroke and major bleeding (MB) among non-valvular atrial fibrillation (NVAF) patients.
Methods
First, claims from the Optum Clinformatics Data Mart database (July 2012-December 2016) were analyzed. Adult NVAF patients with ≥2 NOAC dispensings (index date) were included. The relationship between NOAC adherence (proportion of days covered ≥80%) and stroke/MB 1-year post-index was evaluated using adjusted Cox proportional hazards models. Second, the natural logarithm of hazard ratios (HRs) was multiplied to a literature-derived mean adherence difference between QD and BID NOACs yielding stroke and MB rates. Third, these rates were multiplied by 1-year Kaplan-Meier rates of stroke and MB which yielded the number of strokes prevented and MBs caused. Annual cost savings were evaluated using literature-based stroke ($81,414/patient) and MB ($63,905/patient) cost estimates.
Results
In total, 54,280 patients were included. HRs for adherent vs non-adherent patients were 0.67 (p < .001) for stroke and 1.09 (p = .179) for MB. The claims-derived 1-year Kaplan-Meier rates were 3.0% and 3.4% for strokes and MBs, respectively. For 100,000 AF patients, 64 strokes were prevented (p < .001), and a non-significant number of MBs (n = 15, p < .191) were caused by QD vs BID NOACs annually, which leads to cost savings estimated at $58 million for QD NOACs.
Conclusion
QD NOACs prevented a significant number of strokes and caused no significant increase in MBs compared to BID NOACs, which leads to significant net cost savings for NVAF patients in the US.
Authors
McHorney CA, Peterson ED, Ashton V, Laliberté F, Crivera C, Germain G, Sheikh N, Schein J, Lefebvre P