Cost-Effectiveness of Rivaroxaban Compared to Warfarin for Stroke Prevention in Atrial Fibrillation

BACKGROUND AND OBJECTIVES: Rivaroxaban is noninferior to warfarin for preventing stroke or systemic embolism in patients with high-risk atrial fibrillation (AF) and is associated with a lower rate of intracranial hemorrhage (ICH). We assessed the cost-effectiveness of rivaroxaban compared to adjusted-dose warfarin for the prevention of stroke in patients with nonvalvular AF. METHODS: We built a Markov model using the Korean Health Insurance Review & Assessment Service database. The base-case analysis assumed a cohort of patients with prevalent AF who were aged 18 years or older without contraindications to anticoagulation. RESULTS: Number of patients with CHA2DS2-VASc scores 0, 1 and ≥2 were 56 (0.2%), 1,944 (6.3%) and 28,650 (93.5%), respectively. In patients with CHA2DS2-VASc scores ≥2, the incidence rate of ischemic stroke was 3.11% and 3.76% in warfarin and rivaroxaban groups, respectively. The incidence rates of ICH were 0.42% and 0.15%, and those of gastrointestinal bleeding were 0.32% and 0.15% in warfarin and rivaroxaban, respectively. Patients with AF treated with rivaroxaban lived an average of 11.8 quality-adjusted life years (QALYs) at a lifetime treatment cost of $20,886. Those receiving warfarin lived an average of 11.4 QALYs and incurred costs of $17,151. Patients with rivaroxaban gained an additional 0.4 QALYs over a lifetime with an additional cost of $3,735, resulting in an incremental cost-effectiveness ratio of $9,707 per QALY. CONCLUSIONS: Patients who had been treated with rivaroxaban may be a cost-effective alternative to warfarin for stroke prevention in Korean patients with AF.

Cost-Effectiveness of Rivaroxaban Compared to Warfarin for Stroke Prevention in Atrial Fibrillation

BACKGROUND AND OBJECTIVES@#Rivaroxaban is noninferior to warfarin for preventing stroke or systemic embolism in patients with high-risk atrial fibrillation (AF) and is associated with a lower rate of intracranial hemorrhage (ICH). We assessed the cost-effectiveness of rivaroxaban compared to adjusted-dose warfarin for the prevention of stroke in patients with nonvalvular AF.@*METHODS@#We built a Markov model using the Korean Health Insurance Review & Assessment Service database. The base-case analysis assumed a cohort of patients with prevalent AF who were aged 18 years or older without contraindications to anticoagulation.@*RESULTS@#Number of patients with CHA2DS2-VASc scores 0, 1 and ≥2 were 56 (0.2%), 1,944 (6.3%) and 28,650 (93.5%), respectively. In patients with CHA2DS2-VASc scores ≥2, the incidence rate of ischemic stroke was 3.11% and 3.76% in warfarin and rivaroxaban groups, respectively. The incidence rates of ICH were 0.42% and 0.15%, and those of gastrointestinal bleeding were 0.32% and 0.15% in warfarin and rivaroxaban, respectively. Patients with AF treated with rivaroxaban lived an average of 11.8 quality-adjusted life years (QALYs) at a lifetime treatment cost of $20,886. Those receiving warfarin lived an average of 11.4 QALYs and incurred costs of $17,151. Patients with rivaroxaban gained an additional 0.4 QALYs over a lifetime with an additional cost of $3,735, resulting in an incremental cost-effectiveness ratio of $9,707 per QALY.@*CONCLUSIONS@#Patients who had been treated with rivaroxaban may be a cost-effective alternative to warfarin for stroke prevention in Korean patients with AF.

Short-term Effect of Ambient Air Pollution on Emergency Department Visits for Diabetic Coma in Seoul, Korea / 예방의학회지

OBJECTIVES: A positive association between air pollution and both the incidence and prevalence of diabetes mellitus (DM) has been reported in some epidemiologic and animal studies, but little research has evaluated the relationship between air pollution and diabetic coma. Diabetic coma is an acute complication of DM caused by diabetic ketoacidosis or hyperosmolar hyperglycemic state, which is characterized by extreme hyperglycemia accompanied by coma. We conducted a time-series study with a generalized additive model using a distributed-lag non-linear model to assess the association between ambient air pollution (particulate matter less than 10 μm in aerodynamic diameter, nitrogen dioxide [NO2], sulfur dioxide, carbon monoxide, and ozone) and emergency department (ED) visits for DM with coma in Seoul, Korea from 2005 to 2009. METHODS: The ED data and medical records from the 3 years previous to each diabetic coma event were obtained from the Health Insurance Review and Assessment Service to examine the relationship with air pollutants. RESULTS: Overall, the adjusted relative risks (RRs) for an interquartile range (IQR) increment of NO2 was statistically significant at lag 1 (RR, 1.125; 95% confidence interval [CI], 1.039 to 1.219) in a single-lag model and both lag 0-1 (RR, 1.120; 95% CI, 1.028 to 1.219) and lag 0-3 (RR, 1.092; 95% CI, 1.005 to 1.186) in a cumulative-lag model. In a subgroup analysis, significant positive RRs were found for females for per-IQR increments of NO2 at cumulative lag 0-3 (RR, 1.149; 95% CI, 1.022 to 1.291). CONCLUSIONS: The results of our study suggest that ambient air pollution, specifically NO2, is associated with ED visits for diabetic coma.