Background: Several studies have reported the epidemiology of immune thrombocytopenia (ITP) among children in the United States and other countries. However, recent trends in ITP among hospitalized children and hospital course remain unknown at a national level in the United States.
Method: Hospital discharge records of patients with ITP aged 19 years and younger were obtained for the years 2003, 2006, 2009, and 2012 using the Kids' Inpatient Database. Data were weighted to estimate the annual hospitalization rates in the United States with trend analyses. Multivariable regression models were used to ascertain trends of health care utilizations, hospitalization costs, and length of stay.
Results: Total annual hospitalization rates due to ITP ranged from 6.13 per 100,000 children in 2003 to 6.22 per 100,000 children in 2012 (Ptrend=0.86). The lowest proportions of hospitalizations were observed in August. The proportions of inpatients treated with intravenous immunoglobulin increased from 18.5% in 2003 to 39.9% (Ptrend< 0.001), while those examined with bone marrow aspiration decreased from 7.8% in 2003 to 6.5% in 2012 (Ptrend=0.01). Total hospitalization costs and length of stay changed from $6147 and 3.78 days in 2003 to $9328 and 2.55 days in 2012.
Conclusions: We provided insights of epidemiology of ITP and health care utilizations in the United States. Further studies, including cost-effective analyses, will be required to justify the increasing trends in health care costs and intravenous immunoglobulin.