Abstract
Half of older patients with diffuse large B-cell lymphoma (DLBCL) receiving curative-intent treatment are frail. Understanding the differences in health care utilization including costs between frail and nonfrail patients can inform appropriate models of care. A retrospective cohort study was conducted using population-based data in Ontario, Canada. Patients aged ≥66 years with DLBCL who received frontline curative-intent chemoimmunotherapy between 2006 and 2017 were included. Frailty was defined using a cumulative deficit-based frailty index. Health care utilization and costs were grouped into 5 phases: (1) 90 days preceding first treatment; (2) early treatment (0 to +90 days after starting treatment); (3) late treatment (+91 to +180 days); (4) follow-up (+181 to -181 days before death); and (5) end of life (last 180 days before death). Costs were standardized to 30-day intervals (2019 Canadian dollars). A total of 5527 patients were included (median age, 75 years; 48% female). A total of 2699 patients (49%) were classified as frail. The median costs for frail vs nonfrail patients per 30 days based on phase of care were (1) $5683 vs $2586 ; (2) $13 090 vs $11 256; (3) $5734 vs $4883; (4) $1138 vs $686; and (5) $11 413 vs $9089; statistically significant in all phases. In multivariable modeling, frail patients had higher rates of emergency department visits and hospitalizations and increased costs than nonfrail patients through all phases except end-of-life phase. During end-of-life phase, a substantial portion of patients (n = 2569 [84%]) required admission to hospital; 684 (27%) required intensive care unit admission. Future work could assess whether certain hospitalizations are preventable, particularly for patients identified as frail.