Epidemiology and Clinical Characteristics of Hemophilia in Korea - Report of the Korean Bleeding Disorder Registry (KBDR)

Background: Hemophilia is the rare bleeding disorders. To investigate the epidemiology, natural history and medical environment of hemophilia, the patient registry is the pivotal research design. Many developed countries have their own registry data and published valuable clinical data on the bleeding disorders. For now, there was no nationwide bleeding disorder registry except for the data from the registration program of Korea Hemophilia Foundation (KHF). We developed the first registry for the bleeding disorders in Korea with the funding from the Korean Society of Pediatric Hemato-Oncology (KSPHO) and KHF. We reported the initial interim results on the registry at International Conference of Korean Society of Hematology (ICKSH) in Apr 2022. Here we report the follow-up results on the hemophilia from the registry

Method: We developed the registry platform using iCReaT(Internet based Clinical Research and Trial management system) operated by National Institute of Health in Korea. The registry was designed as the combined retrospective and prospective study for bleeding disorders. At the first stage we first collected data in retrospective fashion to overview the clinical status and epidemiology of bleedingdisorders in Korea. The data was collected under the approval of Institutional Review Board at each participating institution.

Results: As of July 2022, total 625 patients were registered and this is about 1 of thirds of the population of hemophilia in Korea. The current age of this cohort was mean 29.7 ± 19.9, median 26.5 [IQR, 12.7;44.1] years old. Geographic distribution was Seoul (142, 22.7%), Gyunggi (133, 21.3%), Gwangju (101, 16.1%), Chonnam (96, 15.4%), Inchon 53 (8.4%), Ulsan 18 (2.9%) and others. The types of hemophilia were hemophilia A (409, 65.4%), hemophilia B (164, 26.4%), factor 7 deficiency 17 (2.7%), hemophilia C (15, 2.4%), and others. For the severity of hemophilia, 56.7% and 47.0% of hemophilia A and B were severe hemophilia, respectively. In 431 patients, only 50 patients (8%) had genetic variant information. For proportion of prophylaxis, 68.7% of hemophilia A and 51.8% of hemophilia B received prophylaxis. Total 109 patients underwent joint operation for arthropathy. For viral infection, the patients had hepatitis C in 127, hepatitis B in 59 patients and HIV in 4 patients.
Conclusion: In this interim analysis of registry, 625 patients were registered. We described the baseline characteristics of hemophilia registry. This registry data will contribute the better understating on the detailed features of hemophilia in Korea and be cornerstone for further clinical studies to improve survival and quality of life of hemophilia.