Using non-vitamin K oral anticoagulants in specific patient populations: a study of Korean cases

Pragmatic Clinical Studies: An Emerging Clinical Research Discipline for Improving Evidence-Based Practice of Cardiovascular Diseases in Asia

Pragmatic clinical studies, an emerging clinical research discipline, include a wide range of studies that are largely embedded with routine clinical practice and aim to evaluate the comparative effectiveness and safety of different clinical intervention strategies. Increased availability and quality of electronic medical/health records drives the development of pragmatic clinical studies. In this review, we describe evolution of the conceptual framework of pragmatic clinical studies and share perspectives on the importance of pragmatic clinical studies in evidence-based practice for cardiovascular diseases, as a complement to conventional randomized controlled trials. We also highlight specific needs of pragmatic clinical studies in improving evidence-based practice for cardiovascular disease in Asian countries. The main challenges of pragmatic clinical studies are discussed briefly in this review.

Oral anticoagulation patterns and prognosis in octogenarian patients with atrial fibrillation

The relationship between oral anticoagulants (OACs) and prognosis in elderly patients with atrial fibrillation (AF) has not been adequately explored. In this retrospective cohort study, we identified subjects aged over 80 from a database of 1140 AF patients discharged from the cardiology ward of a single tertiary center between 2015 and 2018. We examined the OAC treatment of octogenarian patients at discharge [VKA (vitamin K antagonist), NOAC (non-vitamin K antagonist oral anticoagulant), no OAC treatment]. We analyzed follow-up data of patients on OAC at discharge. The primary endpoint was all-cause death. The secondary endpoint was the incidence of stroke and major bleeding. The association of NOAC versus VKA treatment with these endpoints was assessed with multivariable Cox regression, using the VKA group as reference. A total of 330 octogenarian patients with AF were included with a mean (± SD) age of 83.9 ± 3.5 years. At discharge, 53.3% received a NOAC, 30% a VKA, and 16.7% no OAC. Patients on OAC were followed-up over a median of 2.6-years . The adjusted risk of all-cause death was not different in the NOAC group, compared with the VKA group (hazard ratio [HR], 0.72; 95% confidence intervals [CI] 0.50-1.03; P = 0.07). The risk of stroke or major bleeding was not different either (all P > 0.05). In conclusion, in this cohort of post-discharge octogenarian patients with AF, the risk for all-cause death was similar in NOAC versus VKA users, after adjustment for baseline covariates. No differences in stroke and major bleeding events among these treatment groups were revealed.

Epidemiology of Venous Thromboembolism and Treatment Pattern of Oral Anticoagulation in Korea, 2009-2016: a Nationwide Study Based on the National Health Insurance Service Database

BACKGROUND

The annual incidence of venous thromboembolism (VTE) is increasing, and the treatment pattern of oral anticoagulants (OACs) has changed with introduction of new oral anticoagulants (NOACs). The aims of this study were to assess the annual incidence of VTE in a Korean population and the change of treatment pattern with availability of NOACs using a population-based database.

METHODS

Using the Korean National Health Insurance Services database, we identified patients diagnosed with VTE between 2009 and 2016. The annual prevalence of VTE and clinical characteristics and treatment pattern were investigated. The annual incidence of VTE was calculated using direct and indirect methods using the estimated Korean population in 2009 as the reference.

RESULTS

The annual incidence of VTE in Korean has increased yearly from 23.9 per 100,000 in 2009 to 42.2 in 2016. The overall rate of OAC prescription for VTE treatment increased from 55.9% to 68% in the same time period. The rate of initiation of NOAC treatment greatly increased, particularly from 2013 onwards, with a 20-fold increase from 2009 to 2016 (2.1% vs. 54.3%).

CONCLUSIONS

The annual incidence of VTE in Korea increased by almost two-fold from 2009 to 2016. The rate of initiation of NOAC treatment has increased substantially since 2013, and these agents have surpassed VKAs as the anticoagulant of choice for VTE. This temporal pattern of OAC prescription is consistent with the current clinical guidelines, which indicate NOACs over the warfarin in patients with VTE.