Standard of Care in Patients with Immune Thrombocytopenic Purpura: A Retrospective Chart Analysis.

A retrospective chart review has value for providing a preliminary understanding of a standard of care for a given disease. Most importantly, it can serve as a pilot study to help clarify a research question, determine appropriate sample size, and identify feasibility issues for a future prospective study. The goal of our analysis was to characterize the standard of care in a group of patients with immune thrombocytopenic purpura (ITP) based on a retrospective review of their medical records. ITP is a rare disorder in which platelets are destroyed by autoantibodies and platelet production is impaired. The initial treatment usually involves corticosteroids or intravenous immunoglobulins (IVIG). When initial treatment is unsuccessful, splenectomy is often the next measure. A total of 47 hematologists and oncologists across the US who reported having at least 10 current ITP patients were recruited to participate. Physicians were instructed to pull charts of 3 patients diagnosed with ITP ≥1 to <4 years previously. The following criteria were used to select patient charts: 3 patients for each physician were to have been last examined in January, February, and March 2005, respectively, with birth dates in January or February, March or April, and May or June, respectively. The data extraction tool was a form completed for each patient and provided information on demography, initial diagnosis of ITP, initial treatment, platelet count history, and ITP treatment history. Data were collected between May and September 2005. Charts for a total of 135 patients were examined. Eighty-three patients were women, and 52 were men, reflecting the higher frequency of ITP in the female population. Ages ranged from 18 to 94 years; the wide distribution in age may reflect the observation by some that ITP occurs more frequently with increasing age. Of the original 135 patients, 86 were determined to have chronic ITP (relapse after response to initial therapy) as judged by secondary physician review, and standard of care was analyzed for those patients. The initial ITP therapy was prednisone in 70% (N=60) of the patients and prednisone plus IVIG in 22% (N=19); the remaining 8% (N=7) received "other" initial therapy, including prednisone plus Danazol (3 patients), WinRho (3 patients), and prednisone plus WinRho (1 patient). The number of patients in the "other" category was judged to be too small to provide meaningful information, and the subsequent analysis focused on those in the first two categories. A change in initial therapy was made for 63% of the patients receiving prednisone monotherapy and 63% of those receiving prednisone plus IVIG after an average of 119 and 134 days, respectively. Splenectomy was performed in 20% of the patients receiving prednisone monotherapy and 32% of those receiving prednisone plus IVIG after an average of 149 and 244 days, respectively. Thus, approximately 50% of the patients had a splenectomy within one year after diagnosis. The results of this retrospective chart analysis are being used to help design a future prospective study on standard of care in ITP.