Differences in immunoglobulin utilization when treating patients with primary immune disease in the United States

Primary immune diseases (PI) encompass over 550 disorders that are associated with substantial risk of mortality and morbidity. Emerging evidence demonstrates significant survival disparities in PI among racial minoritized populations. However, published national data on treatment patterns are lacking.

We investigated variations in the use of immunoglobulin replacement therapy (IgGRT) across different geographic regions (Midwest, West, Northeast, South, and other/unknown) and racial groups (Black, Asian, White, and other/unknown) in the United States.

This study analyzed a subset of the Optum deidentified electronic health record dataset, focusing on 3 cohorts of PI patients: common variable immunodeficiency, hypogammaglobulinemia, and combined immunodeficiency (CID). The study compared the treatment status of IgGRT across regional and racial subgroups within each cohort.

Regional differences in IgGRT status were observed among common variable immunodeficiency patients, with treatment rate highest in the West (53.8%) and Midwest (49.9%) and lowest in the South (41.1%) (P < .005). Among patients with hypogammaglobulinemia, a higher proportion of patients in the West (55.8%) received IgGRT than in the South (40.3%) (P < .005). Among patients with CID, those residing in the Midwest (44.4%) had a significantly higher rate of IgGRT utilization compared to the South (32.5%) (P < .005). A greater proportion of White patients with CID (41.3%) received IgGRT compared to African American patients with CID (25.8%) (P < .008).

Our results show differences in IgGRT utilization rates across regional and racial categories within each disease cohort, suggesting potential disparities.