Trends and disparities patterns in CAR-T therapy utilization, inpatient mortality, and adverse events in the United States (2017–2021).

Abstract

e19500 Background: Since the FDA approved CAR-T therapy in August 2017, its utilization has steadily increased. However, limited data exist on variations in adoption across sociodemographic and hospital types. Furthermore, the impact of expanded indications on adoptions, particularly following its approval for multiple myeloma (MM) in 2021, remains unclear. Even less evidence exists regarding trends in adverse events, such as cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), hemophagocytic lymphohistiocytosis (HLH), and tumor lysis syndrome (TLS). Understanding these trends is critical to characterize the real-world adoption of CAR-T therapy and identify potential disparities in uptake. Methods: We analyzed data from the National Inpatient Sample from 2017 to 2021.CAR-T therapy, indications and adverse outcomes were identified using ICD-10 codes. We used a serial cross-sectional study design. Statistical significance for overall trends was evaluated using generalized least squares (GLS) regression statistical methods, with p-trend values considered significant at p < 0.05. Line and stacked graphs were created using R to visualize changes. Results: Utilization of CAR-T therapy increased significantly, from 70 cases in 2017 to 3,195 cases in 2021 (P = 0.008). Non-Hodgkin lymphoma (NHL) remained the most common indication (57.1- 71.9%). Notably, multiple myeloma (MM) emerged as the second most common indication by 2021 (18.8%), surpassing leukemia (12.2%). Whites constituted the majority of CAR-T recipients (57.1–74.1%), followed by Hispanics (7.1–14.1%) and other racial groups (5.7–35.7%). Highest income patients consistently compose the majority of CAR-T receipts (27.8 - 37.4%). Initially, patients aged 18–64 accounted for most CAR-T recipients (~60%), however, uptake among those aged ≥65 increased substantially, nearly equaling younger patients by 2021. Medicare coverage rose from 25.2% in 2017 to 38.5% in 2021, consistent with an increased proportion of older patients. Most CAR-T therapies were administered in large hospitals (~70%) with stable distribution patterns over time. Inpatient mortality remained stable at ~3%, with a temporary peak of 5.2% in 2018. CRS incidence rose significantly, from 17.2% in 2017 to 61.2% in 2021, ICANS and TLS exhibited an initial upward trend followed by a decline, while HLH incidence remained stable. Conclusions: CAR-T therapy utilization has significantly increased, particularly among the elderly and for MM indications. Disparities persist, with white and higher-income patients predominating, Inpatient mortality has stabilized, while CRS incidence has risen, possibly due to increased awareness and improved coding practice. Further research is needed to explore the factors driving these trends and to ensure equitable access to CAR-T therapy.