Venous Thromboembolism in Children and Young Adults in Korea: Analysis of the Korean Health Insurance Review and Assessment Service Database

BACKGROUND: Venous thromboembolism (VTE) is very rare in childhood. Nevertheless, its incidence has increased recently. This study aimed to identify risk factors for developing thrombosis in childhood cancers and other childhood diseases through the Korean Health Insurance Review and Assessment Service database. METHODS: Data were extracted from the Korean Health Insurance Review and Assessment Service database. Children and young adults from 1 month to 29 years of age were eligible, and 21,747 cases of VTE between January 2008 and December 2016 were identified. RESULTS: The VTE incidence was high in children younger than 1 year of age. After 1 year of age, its incidence decreased rapidly and gradually increased. The VTE incidence for children between 0 and 1 year of age was 10.23-fold higher than that for those between 1 and 5 years of age. Annual VTE incidence increased by year. The age-standardized annual incidence rates were 9.98 per 100,000 population in 2008 and 22.53 per 100,000 population in 2016. The age-standardized annual incidence rate increased 2.25-fold during the 8 years. The lower extremity was the most common site of venous thrombosis. CONCLUSION: The incidence of VTE in a population younger than 30 years was 13.11 per 100,000 persons in Korea. We found a bimodal age distribution of the VTE incidence with peaks at infancy and again after 16 years. The incidence of portal vein thrombosis was high in infants, and infection and malignancy were the most common comorbidities in patients with VTE.