Treatment and discharge patterns among patients hospitalized with non-valvular atrial fibrillation transitioning from the inpatient to outpatient setting.

OBJECTIVE: To evaluate inpatient oral anticoagulant (OAC) treatment, discharge location, and post-discharge OAC treatment for patients hospitalized with non-valvular atrial fibrillation (NVAF). RESEARCH DESIGN AND METHODS: Retrospective study using claims data linked to hospital electronic health records (EHR). Patients (n = 2,484) were hospitalized with a primary (38%) or secondary (62%) diagnosis of AF without evidence of mitral valvular heart disease or valve replacement between January 2009 and September 2013. Inpatient OAC treatment was identified from EHR data. MAIN OUTCOME MEASURES: Inpatient and post-discharge OAC treatment [direct OAC (DOAC; apixaban, rivaroxaban, dabigatran), warfarin, no OAC] and discharge location (long-term care, home health-care, home self-care). RESULTS: Mean age was 72.6 years, 61.2% were male, and 89.5% had a CHA2DS2-VASc score ≥2. Overall, 6.4% received a DOAC, 38.0% warfarin, and 55.6% no OAC during hospitalization. Compared to other treatment groups, patients receiving DOAC were younger and more likely to be male. The majority (72.2%) were discharged to home health-care, 13.2% home self-care, and 6.0% long-term care. Among patients who were treated with warfarin during hospitalization, 40.3% filled a warfarin prescription within 30 days post-discharge, whereas among patients who were treated with a DOAC, 52.4% filled a DOAC prescription within 30 days post-discharge. Some NVAF patients not treated with an OAC during hospitalization filled a prescription for warfarin (18.0%) or DOAC (1.9%) within 30 days post-discharge. Results were similar among patients with CHA2DS2-VASc score ≥2. CONCLUSIONS: Most patients hospitalized for NVAF were discharged to home support, and the majority did not have OAC treatment during hospitalization or the 30 days post-discharge. Additional investigation should be conducted on trends beyond 30 days post-hospitalization, and the reasons for not receiving anticoagulation therapy in patients at moderate-to-severe risk of stroke or systemic embolism. Helping to avoid preventable strokes is an important goal for public health.

Risk of stroke/systemic embolism, major bleeding and associated costs in non-valvular atrial fibrillation patients who initiated apixaban, dabigatran or rivaroxaban compared with warfarin in the United States Medicare population.

OBJECTIVE: To compare the risk and cost of stroke/systemic embolism (SE) and major bleeding between each direct oral anticoagulant (DOAC) and warfarin among non-valvular atrial fibrillation (NVAF) patients. METHODS: Patients (≥65 years) initiating warfarin or DOACs (apixaban, rivaroxaban, and dabigatran) were selected from the Medicare database from 1 January 2013 to 31 December 2014. Patients initiating each DOAC were matched 1:1 to warfarin patients using propensity score matching to balance demographics and clinical characteristics. Cox proportional hazards models were used to estimate the risks of stroke/SE and major bleeding of each DOAC vs. warfarin. Two-part models were used to compare the stroke/SE- and major-bleeding-related medical costs between matched cohorts. RESULTS: Of the 186,132 eligible patients, 20,803 apixaban-warfarin pairs, 52,476 rivaroxaban-warfarin pairs, and 16,731 dabigatran-warfarin pairs were matched. Apixaban (hazard ratio [HR] = 0.40; 95% confidence interval [CI] 0.31, 0.53) and rivaroxaban (HR = 0.72; 95% CI 0.63, 0.83) were significantly associated with lower risk of stroke/SE compared to warfarin. Apixaban (HR = 0.51; 95% CI 0.44, 0.58) and dabigatran (HR = 0.79; 95% CI 0.69, 0.91) were significantly associated with lower risk of major bleeding; rivaroxaban (HR = 1.17; 95% CI 1.10, 1.26) was significantly associated with higher risk of major bleeding compared to warfarin. Compared to warfarin, apixaban ($63 vs. $131) and rivaroxaban ($93 vs. $139) had significantly lower stroke/SE-related medical costs; apixaban ($292 vs. $529) and dabigatran ($369 vs. $450) had significantly lower major bleeding-related medical costs. CONCLUSIONS: Among the DOACs in the study, only apixaban is associated with a significantly lower risk of stroke/SE and major bleeding and lower related medical costs compared to warfarin.

Warfarin Management and Outcomes in Patients with Nonvalvular Atrial Fibrillation Within an Integrated Health Care System.

BACKGROUND: Warfarin is a common treatment option to manage patients with nonvalvular atrial fibrillation (NVAF) in clinical practice. Understanding current pharmacist-led anticoagulation clinic management patterns and associated outcomes is important for quality improvement; however, currently little evidence associating outcomes with management patterns exists. OBJECTIVES: To (a) describe warfarin management patterns and (b) evaluate associations between warfarin treatment and clinical outcomes for patients with NVAF in an integrated health care system. METHODS: A retrospective cohort study was conducted among NVAF patients with warfarin therapy between January 1, 2006, and December 31, 2011, using Kaiser Permanente Southern California data, and followed until December 31, 2013. Management patterns related to international normalized ratio (INR) monitoring, anticoagulation clinic pharmacist intervention (consultation), and warfarin dose adjustments were investigated along with yearly attrition rates, time-in-therapeutic ranges (TTRs), and clinical outcomes (stroke or systemic embolism and major bleeding). Descriptive statistics and multivariable Cox proportional hazard models were used to determine associations between TTR and clinical outcomes. RESULTS: A total of 32,074 NVAF patients on warfarin treatment were identified and followed for a median of 3.8 years. About half (49%) of the patients were newly initiating warfarin therapy. INR monitoring and pharmacist interventions were conducted roughly every 3 weeks after 6 months of warfarin treatment. Sixty-three percent of the study population had ≥ 1 warfarin dose adjustments with a mean (SD) of 6.7 (6.3) annual dose adjustments. Warfarin dose adjustments occurred at a median of 1 day (interquartile ranges [IQR] 1-3) after the INR measurement. Yearly attrition rate was from 3.3% to 6.3% during the follow-up, and median (IQR) TTR was 61% (46%-73%). Patients who received frequent INR monitoring (≥ 27 times per year), pharmacist interventions (≥ 24 times per year), or frequently adjusted warfarin dose (≥ 11 times per year) consistently showed poor TTRs (mean TTR for the highest quartiles was 45.3%-48.3%). A higher TTR was associated with a lower risk of clinical outcomes regardless of frequency of INR monitoring, pharmacist interventions, or number of dose adjustments. Patients whose TTRs were < 65%, even with frequent pharmacist interventions, had similar stroke or systemic embolism event rates, as compared with patients with TTRs < 65% and less frequent interventions (1.88 vs. 1.54 stroke or systemic embolism rates per 100 person-years, respectively, P = 0.78). The lowest TTR quartile (< 46%) was associated with a 3 times higher risk of stroke or systemic embolism (hazard ratio [HR] = 3.19, 95% CI = 2.71-3.77) and a 2 times higher risk of major bleeding (HR = 2.10, 95% CI = 1.96-2.24) compared with the highest TTR quartile (≥ 73%). CONCLUSIONS: Despite close monitoring with timely warfarin dose adjustments, there were still a substantial number of challenging patients whose TTRs were suboptimal despite a higher number of pharmacist interventions. These patients eventually experienced more stroke or systemic embolism and bleeding events among NVAF patients managed by anticoagulation clinics. New individualized treatment or management strategies for patients who are not able to reach optimal therapeutic ranges are necessary to improve outcomes. DISCLOSURES: This research and manuscript were funded by Bristol-Myers Squibb Company and Pfizer. Authors from Bristol-Myers Squibb Company and Pfizer participated in the design of the study, interpretation of the data, review/revision of the manuscript, and approval of the final version of the manuscript. An received a grant for research support from Bristol-Myers Squibb/Pfizer. Niu, Rashid, and Zheng received a grant from Bristol-Myers Squibb/Pfizer to their institutions for salary reimbursement. Vo, Singh, and Aranda are employed by Bristol-Myers Squibb; Bruno was employed by Bristol-Myers Squibb at the time of this study. Mendes and Dills are employed by Pfizer, and Mendes was a member of the Pfizer Cardiovascular and Metabolic Field Medical Team during the time of this study. Lang, Jazdzewski, and Le have no known conflicts of interest to report. Study concept and design were contributed primarily by An and Rashid, along with the other authors. Niu took the lead in data collection, along with Zheng, and data interpretation was performed by An, along with Mendes and Dills, with assistance from the other authors. The manuscript was written by An and revised by Mendes, Dills, Vo, Singh, Bruno, and Aranda, along with Lang, Le, and Jazdezewski. Part of this study's findings was presented at the CHEST 2015 Annual Meeting in Montreal, Canada, on October 28, 2015.