Phase‐specific risks of outpatient visits, emergency visits, and hospitalizations during Children's Oncology Group‐based treatment for childhood acute lymphoblastic leukemia: A population‐based study

BACKGROUND: Therapy for childhood acute lymphoblastic leukemia (ALL) is associated with substantial health care utilization and burden on families. Little is known about health care utilization during specific treatment phases. PROCEDURES: We identified children with ALL diagnosed during 2002-2012 in Ontario, Canada and treated according to Children's Oncology Group (COG) protocols. Disease and treatment data were chart abstracted. Population-based health care databases identified all outpatient visits, emergency department (ED) visits, and hospitalizations. In addition to comparing standard and intensified versions of treatment phases, we compared patients receiving different steroids (dexamethasone vs. prednisone) and different versions of interim maintenance (IM) (Capizzi vs. high-dose methotrexate [HD-MTX]). RESULTS: Six hundred thirty-seven children met inclusion criteria. During intensified consolidation, 76.2% of patients were hospitalized at least once, compared to only 32.3% of patients receiving standard consolidation (p < .0001). Similarly, 72.9% of patients receiving intensified delayed intensification (DI) were hospitalized during this phase compared to 50.3% of patients receiving standard DI (p < .0001). Among patients receiving a four-drug induction, those receiving dexamethasone had an 85% higher rate of ED visits (adjusted rate ratio [aRR] 1.85, 95th confidence interval [95CI] 1.14-3.00; p = .01) and a 44% higher rate of hospitalization (aRR 1.44, 95CI 1.24-1.68) compared to those receiving prednisone. Among high-risk B-ALL and T-ALL patients in IM, Capizzi MTX was not associated with an increased rate of ED visits versus HD-MTX. CONCLUSIONS: These results can be used to inform anticipatory guidance for families, particularly those undergoing intensified therapy. Our results also suggest that increased toxicity rates associated with dexamethasone during Induction seen in clinical trials reflect real-world practice.