A cost-analysis model for anticoagulant treatment in the hospital setting

Shorter Hospital Stays and Lower Costs for Rivaroxaban Compared With Warfarin for Venous Thrombosis Admissions

Background

Venous thromboembolism, including deep vein thrombosis and pulmonary embolism, results in a substantial healthcare system burden. This retrospective observational study compared hospital length of stay (LOS) and hospitalization costs for patients with venous thromboembolism treated with rivaroxaban versus those treated with warfarin.

Methods and Results

Hospitalizations for adult patients with a primary diagnosis of deep vein thrombosis or pulmonary embolism who were initiated on rivaroxaban or warfarin were selected from MarketScan's Hospital Drug Database between November 1, 2012, and December 31, 2013. Patients treated with warfarin were matched 1:1 to patients treated with rivaroxaban using exact and propensity score matching. Hospital LOS, time from first dose to discharge, and hospitalization costs were reported descriptively and with generalized linear models (GLMs). The final study cohorts each included 1223 patients (751 with pulmonary embolism and 472 with deep vein thrombosis). Cohorts were well matched for demographic and clinical characteristics. Mean (±SD) LOS was 3.7±3.1 days for patients taking rivaroxaban and 5.2±3.7 days for patients taking warfarin, confirmed by GLM‐adjusted results (rivaroxaban 3.7 days, warfarin 5.3 days, P<0.001). Patients with provoked venous thromboembolism admissions showed longer LOSs (rivaroxaban 5.1±4.5 days, warfarin 6.5±5.6 days, P<0.001) than those with unprovoked venous thromboembolism (rivaroxaban 3.3±2.4 days, warfarin 4.8±2.8 days, P<0.001). Days from first dose to discharge were 2.4±1.7 for patients treated with rivaroxaban and 3.9±3.7 for patients treated with warfarin when initiated with parenteral anticoagulants (P<0.001), and 2.7±1.7 and 3.7±2.1, respectively, when initiated without parenteral anticoagulants (P<0.001). Patients initiated on rivaroxaban incurred significantly lower mean total hospitalization costs ($8688±$9927 versus $9823±$9319, P=0.004), confirmed by modeling (rivaroxaban $8387 [95% confidence interval, $8035–$8739]; warfarin $10 275 [95% confidence interval, $9842–$10 708]).

Conclusions

Rivaroxaban was associated with significantly shorter hospital LOS and lower hospitalization costs compared with warfarin.

A cost-utility analysis for catheter ablation of atrial fibrillation in combination with warfarin and dabigatran based on the CHADS2 score in Japan

BACKGROUND

We aimed to clarify the cost-effectiveness of an expensive combination therapy for atrial fibrillation (AF) using both catheter ablation and dabigatran compared with warfarin at each CHADS₂ score for patients in Japan.

METHODS

A Markov model was constructed to analyze costs and quality-adjusted life years associated with AF therapeutic options with a time horizon of 10 years. The target population was 60-year-old patients with paroxysmal AF. The indication for anticoagulation was determined according to the Japanese guideline. Anticoagulation-related data were derived from the RE-LY study and the AF recurrence rate was set at 2.7% per month during the first 12 months and at 0.40% per month afterwards. Stroke risk was determined according to AF recurrence, anticoagulation, and CHADS₂ score. The risks for stroke recurrence and stroke death were also considered. Costs were calculated from the healthcare payer's perspective, and only direct medical costs were included.

RESULTS

Warfarin was the most preferred option for patients with a CHADS₂ score of 0 from a health economics aspect. Ablation under warfarin was preferred for a CHADS₂ score of 1-3, while ablation under dabigatran was preferred for a CHADS₂ score ≥4. The quality of life score for AF had the largest impact on the incremental cost-effectiveness ratios in the analysis between the anticoagulation arm and the anticoagulation+ablation arm for a CHADS₂ score of 2. Within the range of the Japanese willingness-to-pay threshold (¥5,000,000), the ablation+warfarin arm became the best option with its probability of 81.7% for a CHADS₂ score of 2; the dabigatran+ablation arm was the most preferred option with its probability of 56.1% for a CHADS₂ score of 4.

CONCLUSIONS

Ablation under dabigatran therapy is an expensive therapeutic option, but it might benefit patients with a low quality of life and a high CHADS₂ score.