Outcomes Associated With Standardized Ideal Body Weight Dosing of Intravenous Immune Globulin in Hospitalized Patients: A Multicenter Study

Background: There are limited outcomes data for ideal body weight (IBW)-based dosing of intravenous immune globulin (human, IVIG) in hospitalized patients. Objective: To investigate clinical outcomes associated with a standardized change from total body weight to IBW-based dosing of IVIG. Methods: This was a retrospective, multicenter, pre-post sequential period analysis. Data from pre-implementation and post-implementation of an IBW-based dosing strategy for IVIG were collected in 2-year periods (October 1, 2012, to August 31, 2014, and October 2, 2014, to October 1, 2016, respectively). The primary outcome was incidence of 30-day hospital readmission. Length of stay (LOS) was analyzed as a secondary outcome. Results: For the 2 study periods, 297 patients were included for analysis. Both groups had similar demographics, IVIG indications, and body weight measurements, but the post-implementation period had a lower median grams per dose as compared with the pre-implementation period (40 vs 30 g, P ≤ 0.01). 30-Day hospital readmission rates were not significantly different (4% vs 9%, P = 0.07). In-hospital all-cause mortality was also not statistically significant (7.7% vs 3.4%, P = 0.11). The 2 study groups had a similar median hospital LOS (8 vs 7.6 days, P = 0.27). Conclusion and Relevance: The implementation of a standardized IBW IVIG dosing strategy was not associated with a statistically significant increase in 30-day hospital readmission or LOS but was associated with significantly fewer grams per dose given. Application of these data may aid in decreasing institutional drug spend without affecting patient outcomes. However, the study was underpowered, and further investigation is necessary to validate these findings.