Study of Treatment Patterns and Consequences of Immune Thrombocytopenic Purpura (ITP).

Standard treatment strategies for chronic immune thrombocytopenic purpura (ITP) in adults include oral steroids, high dose IVIG (intravenous immunoglobulin), Anti-D, or splenectomy (in refractory cases). Although guidelines have been developed, optimal and most frequently applied treatment strategies remain uncertain. In this retrospective administrative claims database study, patient demographics, comorbidities, and treatment characteristics were captured to assist in determining burden of illness on patients with chronic ITP. Patients from five US health plans with medical claims for ITP (ICD-9CM codes 287.3 or 287.5) between 1/1/00 – 2/29/04 were included if they had continuous health plan enrollment 6 months prior to and 12 months after an index diagnosis of ITP. To be considered as chronic, patients also were required to have ≥1 additional drug claims or ITP diagnoses claim(s) six months after the index. Patients with codes for HIV, hepatitis, chemotherapy, or HIT were excluded. A total of 3,743 patients met the study criteria; 53% were females (n=1,969). Mean age was 57 ± 16.9. Patients had a mean follow-up duration of 976 ± 441 days. Mean Deyo-Charlson Comorbidity Indices were 1.2 ± 1.9 pre-index, 2.0 ± 2.4 post-index of a maximum score of 21. Hypertension (62% pre-index; 51% post-index) and coronary heart disease (38% pre-index; 28% post-index) were common comorbidities. Of concomitant medications, most patients were taking antibiotics pre-index (n=3,008) as well as post-index (n=3,316). Twenty-nine percent of patients were hospitalized during follow-up with ITP recorded during the inpatient stay. The mean number of days to drug treatment was 378 ± 376. Among patients who received pharmacological treatment (n=1,834), the most frequently used first-line and second-line therapies were oral corticosteroids (n=1,742) and cyclosporine (n=75), respectively. Among patients treated with oral corticosteroids with ≥1 year follow up, the average time on treatment was 95 days. Further evaluation of the period between the index ITP diagnosis and drug therapy, and pharmacologic interventions for ITP during hospitalizations are underway.