Healthcare Resource Utilization Among Patients With Activated PI3Kδ Syndrome in the United States: A Real-world Assessment by Patient Age

Abstract

ImportanceDespite the known morbidity associated with activated PI3Kδ syndrome (APDS), little is understood about the healthcare resource utilization (HRU) attributable to this condition. ObjectiveTo describe HRU and treatment patterns of patients with APDS by age group (≤11 and ≥12 yrs). MethodsPatients with APDS were identified via genetic testing and tokenized to the Symphony Health Integrated Dataverse database comprising medical/pharmacy claims (10/1/2015–3/31/2021). HRU rates (hospitalizations, emergency room [ER], outpatient, and other visits) per person-year, main reason for HRU visit, and treatment patterns were assessed from the start of patients’ clinical activity to the earliest of end of clinical activity or data availability (observation period). ResultsOf 31 patients with APDS identified, 14 were ≤11 yrs and 17 were ≥12 yrs. The mean±SD observation period was 3.9 ±2.1 and 5.2 ± 1.8 yrs, respectively; mean age was 3.9 ± 2.7 and 29.4 ± 13.1 yrs, respectively. Common clinical manifestations in ≤11 yrs included lymphoproliferation (71.4%), fever (64.3%), allergy (57.1%), otitis media (50.0%), diarrhea (21.4%), and lymphoma (7.1%). Common clinical manifestations in ≥12 yrs included sinusitis (58.8%), bronchitis (58.8%), allergy (47.1%), diarrhea (23.5%), and lymphoma (17.6%). Outpatient visit rates were high overall; ER visits and hospitalization rates were low in both groups, whereas other visit rates were high in ≥12 yrs (Figure 1). Immunoglobulin replacement therapy (IRT)-related HRU accounted for 14.4% and 17.9% of outpatient visits in ≤11 yrs and ≥12 yrs, respectively, and 36.6% and 34.3% of other visits in ≤11 yrs and ≥12 yrs, respectively. Reasons for outpatient visits included enlarged lymph nodes and otitis media in ≤11 yrs and long-term drug therapy, common variable immunodeficiency, and acute sinusitis in ≥12 yrs. IRT was used by 42.9% and 70.6% in ≤11 yrs and ≥12 yrs, respectively. Antibiotic, corticosteroid, and mTor inhibitors were used by 92.9% and 88.2%, 78.6% and 76.5%, and 21.4% and 11.8% in ≤11 yrs and ≥12 yrs, respectively; no rituximab use was observed. [Display omitted] ConclusionsAPDS presents with various complex clinical manifestations requiring intervention. Among patients analyzed, outpatient and other visits were the most commonly used healthcare resources and were often associated with respiratory disease and immunodeficiency management. To our knowledge, this is the first study to assess HRU among patients with APDS using administrative claims data.