Comparison of hospital length of stay between hospitalized non-valvular atrial fibrillation patients treated with either apixaban or warfarin

Abstract

Background. Hospital length of stay (LOS) is an important cost driver for hospitals and payers alike. Hospitalized non-valvular atrial fibrillation (NVAF) patients treated with apixaban may have shorter LOS than those treated with warfarin because of the absence of need for INR monitoring in apixaban. Thus, this study compared hospital LOS between hospitalized NVAF patients treated with either apixaban or warfarin. Methods. This was a retrospective, observational cohort study based on a large US database including diagnosis, procedure, and drug administration information from >600 acute-care hospitals. Patients selected for study were aged ≥18 years and had a hospitalization record with an ICD-9-CM diagnosis code for atrial fibrillation (AF) in any position from 1 January 2013 to 28 February 2014 (index hospitalization). Patients with diagnoses indicative of rheumatic mitral valvular heart disease or a valve replacement procedure during index hospitalization were excluded. Patients were required to have been treated with either apixaban or warfarin, and not treated with rivaroxaban or dabigatran, during index hospitalization. Apixaban patients were propensity score (PS) matched to warfarin patients at a 1:1 ratio, using patient demographic/clinical and hospital characteristics. The study outcome was hospital LOS, calculated as discharge date minus admission date; a sensitivity analysis calculated hospital LOS as discharge date minus first anticoagulant administration date. Sub-analyses were conducted among patients with a primary diagnosis of AF. Results. The study included 832 apixaban patients matched to 832 warfarin patients. Mean [standard deviation (SD)] and median hospital LOS were significantly (p < 0.001) shorter in apixaban patients (4.5 [4.2] and 3 days) than in warfarin patients (5.4 [5.0] and 4). Results were consistent in the sensitivity and sub-analyses. Conclusions. Among NVAF patients, apixaban treatment was associated with shorter hospital LOS when compared with warfarin treatment. These findings may have important clinical and economic implications for hospitals, payers, and patients.

Keywords:

• Atrial fibrillation
• length of stay
• hospitalization
• warfarin
• factor Xa inhibitors

Declaration of interest

This study was sponsored by Bristol-Myers Squibb and Pfizer. Truven Health Analytics was paid by Bristol-Myers Squibb and Pfizer for the development of this manuscript and the work described herein. AM Farr and S Johnston are employees of Truven Health Analytics. Y Jing and J Graham were employees of Bristol Myers Squibb at the time that this study was conducted. J Trocio is an employee of Pfizer Inc. S Singhal and A Bruno are employees of Bristol Myers Squibb. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

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