Abstract
The epidemiology of immune thrombocytopenia (ITP) is not well characterized in the general Korean population. ITP patients from 2010 to 2014 were identified using the Korean Health Insurance Review and Assessment Service (HIRA) database. Patients with diagnosis codes for secondary thrombocytopenia or secondary ITP were excluded if those codes coexisted with ITP code of D693.0 or D693.8. The prevalent cases before 1st July 2010 and incident cases from 1st July 2014 were also excluded to calculate the exact incidence of ITP. Overall age-standardized incidence rates of ITP were 5.42/100,000 person-years (95% CI: 5.33-5.51; women, 6.17 [95% CI, 6.03-6.30]; men, 4.69 [95% CI, 4.57-4.81]).The overall incidence rates of ITP appeared to have a bimodal distribution, with peaks among children (< 10 years) and in those > 70 years of age. Among adults, the age-specific incidence rates increased with age for man, but those were observed to be constant for women (figure 1). Overall, 75.2% of patients needed treatment with the median time from the diagnosis to treatment of 1.7 months (range, 0-53.3 months). First-line therapy consisted of steroids and/or immunoglobulin in 83.6%, immunoglobulin only in 14.5%, and other immunosuppressive agents such as cyclosporine A, azathioprine, mycophenolate mofetil, and danazol in 1.9%. Only 1.0% of patients underwent splenectomy and laparoscopic procedure accounted for 90.5% of these 108 patients. The median age was 46 years (range, 9-77 years) at the time of splenectomy, and 77.8% of patients were female. 58.8% of patients received treatment beyond 6months after initial therapy. Among these patients, the most frequently used therapy was steroid and/or immunoglobulin in 92.6% followed by other immunosuppressive agents in 6.9% and immunoglobulin in 0.5%. Platelet transfusions were given 13.7% of patients and the median numbers of platelets transfused were 12 units (range, 1-2,484 units) during study periods. The usage of thrombopoietin receptor agonists or rituximab couldn't be analyzed because these drugs have not been reimbursed for the treatment of ITP before 2016 in Korea. This population-based study firstly describes the incidence rates of ITP and treatment reality for patients with ITP in Korea.
No relevant conflicts of interest to declare.
Author notes
Asterisk with author names denotes non-ASH members.