BACKGROUND: Overall use of factor VIII (FVIII) and prophylactic use have increased in South Korea over the past decade. However, there are no nationwide outcome data demonstrating its impact. This study aimed to identify patients with haemophilia A (PwHA) and observe trends in joint-related outcomes and life-threatening haemorrhages using national claims data.

METHODS: This serial cross-sectional study analysed claims data from the Health Insurance and Review Assessment in South Korea. PwHA treated with FVIII at least twice between 2007 and 2022 were identified. We observed joint procedures, life-threatening haemorrhages and comorbidities between 2008 and 2021.

RESULTS: The number of identified PwHAs was 1193 in 2008 and 1517 in 2021. The proportion of older adult patients has increased over the past 14 years. The joint procedure rates per 1000 patients were 61.2 (95% CI 48.0‒76.9) in 2008 and 17.1 (11.2‒25.1) in 2021. The rate was highest in patients with a severe phenotype. Annually, less than 2% of patients experienced life-threatening haemorrhages, with approximately 90% of the cases attributed to central nervous system and gastrointestinal bleeding. The prevalence of hypertension and diabetes increased over the years (6% in 2008 and 15% in 2021, and 6% in 2008 and 9% in 2021, respectively).

CONCLUSION: This study revealed previously unreported long-term trends in haemophilia-related outcomes and comorbidities in Korean PwHA. Although the number of older adult patients has increased, joint-related complications have decreased over time. The trends, observed over 14 years, provide valuable insights for enhancing the treatment of PwHA.