Cost-effectiveness of rivaroxaban versus warfarin for treatment of nonvalvular atrial fibrillation in patients with worsening renal function.

BACKGROUND: Nonvalvular atrial fibrillation (NVAF) is highly prevalent and increases the risks of cardiovascular events. In a recent subgroup analysis, treatment response was shown to vary for patients exhibiting worsening renal function (WRF) on-treatment. It is important to understand the cost-effectiveness of novel oral anticoagulant (NOAC) use in this population. METHODS: A cost-effectiveness analysis (CEA) was conducted using a Markov model to determine whether NOAC rivaroxaban treatment is cost-effective relative to warfarin in NVAF patients with on-treatment WRF. Input parameters were sourced from clinical literature including a multicenter clinical trial and subgroup analysis. We studied elderly US male patients at increased risk for stroke (CHADS2 score ≥ 2) undergoing treatment for NVAF and exhibiting WRF. Main outcome measures included total healthcare costs in 2017 US dollars (societal perspective), total quality-adjusted life years (QALYs), incremental cost-effectiveness ratio (ICER), and incremental net monetary benefits (INMB) per-patient. RESULTS: The remaining lifetime use of rivaroxaban is associated with 5.69 QALYs at a cost of $66,075 per patient, while warfarin produced 5.22 QALYs with costs of $78,504 per patient. At a willingness-to-pay (WTP) of $150,000 per QALY, incremental net monetary benefits (INMB) per patient are $83,590. In our population, treatment with warfarin was dominated by rivaroxaban in 99.4% of 10,000 simulations. CONCLUSIONS: Rivaroxaban is likely a dominant treatment over warfarin in elderly US male NVAF patients exhibiting WRF, providing increased QALYs at a decreased overall cost. Application of these findings may require healthcare providers to predict which patients are likely to exhibit WRF.

Impact of obesity on atrial fibrillation ablation: Patient characteristics, long-term outcomes, and complications.

BACKGROUND: There is an association between obesity and atrial fibrillation (AF). The impact of obesity on AF ablation procedures is unclear. OBJECTIVE: The purpose of this study was to evaluate the influence of body mass index (BMI) on patient characteristics, long-term ablation outcomes, and procedural complications. METHODS: We evaluated 2715 patients undergoing 3742 AF ablation procedures. BMI was ≥30 kg/m2 in 1058 (39%) and ≥40 kg/m2 in 129 (4.8%). Patients were grouped by BMI ranges (<25, 25-<30, 30-<35, 35-<40, and ≥40 kg/m2). RESULTS: As BMI increased from <25 to ≥40 kg/m2, age decreased from 65.3 ± 11.2 to 61.2 ± 9.2 years (P < .001), left atrial size increased from 3.91 ± 0.68 to 4.72 ± 0.62 cm (P < .005), and CHADS2 scores increased from 1.24 ± 1.10 to 1.62 ± 1.09 (P < .001). As BMI increased, paroxysmal AF decreased from 48.0% to 16.3% (P < .0001) and there was an increase in dilated cardiomyopathy (from 7.6% to 12.4%; P < .0001), hypertension (from 41.0% to 72.9%; P < .0001), diabetes (from 4.3% to 23.3%; P < .0001), and sleep apnea (from 7.0% to 46.9%; P < .0001). For the entire cohort, for BMI ≥35 kg/m2 the 5-year ablation freedom from AF decreased from 67%-72% to 57% (P = .036). For paroxysmal AF, when BMI was ≥40 kg/m2 ablation success decreased from 79%-82% to 60% (P = .064), and for persistent AF, when BMI was ≥35 kg/m2 ablation success decreased from 64%-70% to 52%-57% (P = .021). For long-standing AF, there was no impact of BMI on outcomes (P = .624). In multivariate analysis, BMI ≥35 kg/m2 predicted worse outcomes (P = .036). Higher BMI did not impact major complication rates (P = .336). However, when BMI was ≥40 kg/m2, minor (from 2.1% to 4.4%; P = .035) and total (from 3.5% to 6.7%; P = .023) complications increased. CONCLUSION: In patients undergoing AF ablation, increasing BMI is associated with more patient comorbidities and more persistent and long-standing AF. BMI ≥35 kg/m2 adversely impacts ablation outcomes, and BMI ≥40 kg/m2 increases minor complications.