A recent study published in JAMA Network Open conducted by Lin et al., investigated the effectiveness and patient-centered outcomes of different oral anticoagulants (OACs) in older adults with atrial fibrillation (Afib), with a particular focus on those with frailty. The study found that apixaban (Eliquis) demonstrated better outcomes compared to rivaroxaban (Xarelto) and warfarin. However, upon critical analysis of the study, several limitations and areas of further investigation emerge.
The study reported that rivaroxaban was associated with a significantly increased risk of spending more than 14 days in the hospital or a skilled nursing facility during the 1-year follow-up, compared to apixaban. Additionally, rivaroxaban had a higher composite risk of ischemic stroke, systemic embolism, major bleeding, or death. Similarly, warfarin was associated with increased risk of spending more than 14 days in a medical facility and combined clinical events. While these findings suggest the superiority of apixaban in terms of patient outcomes, it is important to consider other confounding factors that may have influenced these results.
In the frail subgroup, apixaban demonstrated relatively greater reductions in home time lost and lower composite clinical events compared to rivaroxaban and warfarin. These findings suggest that apixaban may be the preferred OAC for older adults with Afib and frailty. However, it is worth noting that the study did not include comparisons with other direct oral anticoagulants (DOACs) such as dabigatran (Pradaxa) and edoxaban (Savaysa), which are less commonly used in clinical practice. Further research is necessary to determine the effectiveness of these DOACs in frail patients with Afib.
The study found that apixaban had a total annual cost lower than rivaroxaban but higher than warfarin, primarily driven by the cost of the OAC itself. Excluding the cost of the OAC, other costs were lowest with apixaban, highest with rivaroxaban, and intermediate with warfarin. These cost considerations may influence the choice of OAC for older adults with Afib, particularly in healthcare systems with limited resources. However, the study did not provide a comprehensive cost-effectiveness analysis, and further research is needed to evaluate the long-term economic implications of different OACs.
Despite the increasing willingness of older adults with Afib to initiate and adhere to anticoagulant therapy, oral anticoagulants remain underutilized in this population. This underutilization may be due to various factors such as lack of awareness, concerns about bleeding risks, and difficulties in medication management. The study’s findings highlight the need for strategies to improve the appropriate prescription and utilization of OACs in older adults with Afib, especially those who are frail.
The study acknowledges several limitations, including the potential for unmeasured confounding despite statistical adjustments. Important clinical variables such as laboratory test results and use of over-the-counter medications were not available in the administrative claims dataset, which could have influenced the study’s findings. Additionally, the study focused on Medicare fee-for-service beneficiaries and may not be generalizable to other populations. Further research is needed to analyze the impact of dosing, adherence, and drug interactions on the efficacy and safety of different OACs in frail patients with Afib.
The study by Lin et al. provides valuable insights into the comparative effectiveness of OACs in older adults with Afib, particularly in those with frailty. Apixaban emerged as the preferred OAC for this population, demonstrating better patient-centered outcomes and lower costs compared to rivaroxaban and warfarin. However, the study has limitations, and additional research is necessary to fully understand the impact of different OACs on frail patients with Afib. It is crucial to continue exploring strategies to improve the appropriate utilization of OACs in older adults with Afib, addressing the treatment gaps and reducing the risk of adverse outcomes.