Epidemiology

Abstract

ITP is estimated to have incidence between 2.16 and 3.9 per 100,000 person-years. There is a 1.1 to 1.5:1 female to male predominance in the entire ITP patients although ITP was more frequent among males in the age groups less than 5 years and over 75 years old. Intracranial hemorrhage (ICH) is the most devastating bleeding event, and its incidence is 0.37-0.6%. In contrast, recent studies suggest that ITP may have paradoxically an increased risk for thromboembolism. Regarding the treatment of ITP, the rate of splenectomy has been dramatically decreased to only 6% in recent years because patients are increasingly reluctant to undergo splenectomy and new drugs including anti-CD20 monoclonal antibody and thrombopoietin receptor agonists have been developed. Besides the bleeding risk, the infection risk derived from immunosuppressive treatment should be emphasized because bleeding and infection equally contributed to the death of ITP patients.