Burden of hospitalizations in four adolescent and young adult (AYA) cancer survivor populations in the United States, 2006-2020

BACKGROUND: We describe hospitalization rates in adolescent and young adult (AYA) cancer survivors 2-5 years (Y2-Y5) from diagnosis. METHODS: Observational study of AYA cancer survivors diagnosed 2006-2020 was conducted in two healthcare systems [Kaiser Permanente Southern California (n=7889) and Northern California (n=7338)] and two states [California (47,302) and Utah (n=7935)]. Hospitalizations were ascertained from electronic health records and statewide administrative records and stratified by whether pregnancy-related. Hospitalization rates were calculated by cohort. We estimated patient factors associated with hospitalizations using a Poisson model. RESULTS: Most AYA survivors were women (~64% of all cohorts), mean age ~31 years at diagnosis, and non-Hispanic white (range 35.1-81.2%) or Hispanic (range 14.3-40.6%). Overall, 21-24% of AYA survivors experienced >1 hospitalization. Unadjusted hospitalization rates declined from Y2 [range 155.1-243.4 per 1000 person-years (PY)] to Y5 (range 105.8-132.0 PY) (p-trend<0.0001 in all cohorts). Factors associated with increased non-pregnancy related hospitalizations were [range of relative risks (RR)]: non-Hispanic Black race/ethnicity (RR 1.46-1.66 vs non-Hispanic white); public insurance (RR 1.57-1.93 vs commercial/military); receipt of chemotherapy (RR 1.51-1.81), and cancer type-breast (RR 1.69-1.97), cervical (RR 2.30-3.31), colorectal (2.76-3.66), acute lymphoblastic leukemia (RR 2.89-5.19), acute myeloid leukemia (2.11-5.05), and sarcoma (RR 2.70-4.96) (vs thyroid). CONCLUSIONS: While hospitalizations decline as time from diagnosis elapses across health system settings and states, nearly 1 in 5 AYA cancer survivors experience hospitalization in early survivorship. , IMPACT: Hospitalization rates remain elevated in some AYA patient subgroups in early survivorship, highlighting the need to identify AYAs at risk to mitigate unanticipated hospitalizations and costs.