Home Care Use of Intravenous and Subcutaneous Immunoglobulin for Primary Immunodeficiency in the United States

Purpose Utilization reports on immunoglobulin (Ig) use for immunodeficiency in the United States (U.S.) have focused on prescribing practices in hospitals. There have been no large-scale reports on Ig use for immune deficiency in the home. We investigated the use of Ig in 3,187 subjects diagnosed with primary immunodeficiency. Methods Cross-sectional data on 4,580 subjects in the U. S. receiving Ig in 2011 was obtained from a major home care provider. Demographics, route, dose, and frequency of Ig use by subjects with ICD-9 coded primary immunodeficiencies were analyzed. Results Of 4,580 subjects, 3,187 had ICD-9 codes suggesting primary immunodeficiencies; 1,939 (60.8 %) were females and 1,248 (39.2 %) were males, with age ranging from 0 to 95 years. The predominant diagnoses were: common variable immunodeficiency (279.06; n=01,764; 55.3 %), hypogammaglobulinemia (279.00; n=635; 19.9 %), unspecified immunity deficiency (279.3; n=286; 9 %), other selective Ig deficiencies (279.03; n=171; 5.4 %), and agammaglobulinemia (279.04; n=127; 4 %). 54 % of subjects received Ig by the subcutaneous (SC) route, and 46 % by intravenous (IV) route, with more SC use by older subjects. The mean dose prescribed was 483 mg/kg/month, but less Ig was ordered for subjects on SCIg (409 mg/kg/month), as compared to subjects on IVIg (568 mg/kg/month). A highly significant inverse correlation between increasing age and dosage of Ig ordered was found (P=<.0001). Conclusion Analysis of home care use of Ig in primary immune deficiency revealed that the SC route was prescribed more than the IV route, especially for older patients. By either method of administration, less immunoglobulin was prescribed for older subjects.