The Epidemiology of Immune Thrombocytopenia in Taiwan: A Retrospective Analysis of Data from the National Health Database
1 Division of Transfusion Medicine, Department of Medicine, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taiwan.
2 Division of Hematology, Department of Medicine, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taiwan.
3
Department of Life Science, Fu-Jen Catholic University, New Taipei City, Taiwan.
Citation: Tzeon-Jye Chiou, Liang-Tsai. Hsiao, Wang-Fang Tzeng. “The Epidemiology of Immune
Thrombocytopenia in Taiwan: A Retrospective Analysis of Data from the National Health Database”.
American Research Journal of Hematology; 3(1): 1-15.
Abstract
Objectives: This study aimed to investigate the prevalence and current treatment status of immune
thrombocytopenia (ITP) in Taiwan.
Methods: This was a retrospective study conducted using claim data collected from the Bureau of National
Health Insurance (BNHI) of Taiwan from 2003 to 2007. ITP patients were identified using the ICD-9 code, 287.3
(primary thrombocytopenia), with two diagnoses separated by at least 14 days for diagnostic specificity. In
addition, sensitivity analysis was based on 28 (ITP-28) and 84 (ITP-84) days.
Results: ITP prevalence ranged from 10.35 to 11.02 (per 100,000 individuals) with an annual number of 2,300
to 2,500 patients, and sensitivity analyses using ITP-28 and ITP-84 criteria showed that the prevalence were
“9.52 to 10.35” and “6.87 to 8.14” in 5,445 ITP patients, respectively. The median age of ITP-14 patients was
46.5 years. In children, the female-to-male ratio was nearly equal (0.93), whereas in adults, it was 1.91. About
3.9% received splenectomy, of which 64.3% were responsive to splenectomy. Further, 92.6% were responsive
to steroids. The average costs per visit were US$ 36 and US$ 1,700 for outpatients and inpatients, respectively.
For steroid-responsive patients, the mean costs for clinic visits and hospitalization were US$ 35 and US$ 1,415,
respectively. In contrast, the medical expense for steroid-refractory patients was approximately one and a half
times the costs for responsive patients (inpatient: US$ 54; outpatient: US$ 2,349). For splenectomy-responsive
inpatients, the average expenses prior to, at, and after splenectomy were US$ 1,877, 5,476, and 2,061, respectively.
For splenectomy-refractory inpatients, the costs were comparable to those of responsive patients (P> 0.05).
On the contrary, there were significant differences between the expenditure for splenectomy-responsive and
-refractory outpatients. Among ITP patients in Taiwan, 7.4% and 6.4% had hepatitis B virus (HBV) and hepatitis
C virus (HCV) infections, respectively, and 1.5% had both HBV and HCV infections. Patients with HBV were
significantly high in the splenectomy group (splenectomy vs. non-splenectomy 11.7% vs. 7.2%, P = 0.01), and
those who were more responsive to splenectomy had a low HCV infection rate, i.e., 14.5% had HCV infection in
splenectomy-refractory group vs. 4.38% in splenectomy-responsive group (P = 0.02).
Conclusions:The epidemiology of ITP in Taiwan, including the age and sex, was comparable with that in western
countries, except with lower incidence of splenectomy in our patients. The status of HBV and HCV infection in
splenectomized patients should be closely monitored. The medical expenditure in Taiwan was much lower
than that in western countries. We suggest that novel agents or more aggressive treatment strategies should be
further explored or considered in Taiwan