Treatment Patterns and Bleeding Risk of Anticoagulants in Patients With Venous Thromboembolism in Korea

Treatment Patterns and Clinical Outcomes Among Venous Thromboembolism Patients Treated With Anticoagulants After the Entry of Non-vitamin K Antagonist Oral Anticoagulants in Korea

This study is a retrospective, observational, nationwide population-based cohort study utilizing the South Korea's Health Insurance and Review Assessment Service (HIRA) database. The aims of this study are to describe the sociodemographic and clinical characteristics of patients with venous thromboembolism according to their anticoagulant treatment (parenteral anticoagulants, warfarin, or non-vitamin K antagonist oral anticoagulants), to describe the treatment patterns related to anticoagulants, and to examine the risk of major bleeding according to the specific type of oral anticoagulants. The study will be conducted in two phases: Phase I for descriptive study and Phase II for comparative study.

Inclusion Criteria:

1. Incident VTE diagnosis in an inpatient or outpatient setting between 1 Mar 2013 and 30 Jun 2019
2. Received anticoagulation therapy (all medication codes for anticoagulants approved for VTE in Korea; UFH, LMWH, warfarin, and NOACs) within 30 days of their VTE diagnosis (the index date will be defined as the date of treatment initiation with anticoagulants)
3. Aged ≥18 years at index date

Exclusion Criteria:

1. Had a record of VTE diagnosis within the 12-month period prior to the index VTE encounter.
2. Diagnosed with atrial fibrillation/flutter, mechanical heart valve replacement or mitral stenosis anytime prior to index date
3. Had a record of Inferior Vena Cava filter anytime prior to index date
4. Received anticoagulatory therapy within the 12-month period prior to index VTE encounter
5. Prescribed two different anticoagulants on the same index date
6. Had a record of pregnancy within the 9-month period prior to index date
7. Had a record of active cancer within the past 6 months of period prior to index date