Association of febrile neutropenia (FN) risk factors (RFs) with incident FN in U.S. commercial and Medicare advantage patients receiving intermediate-risk chemotherapy for non-myeloid cancers between 2009 and 2019.

Abstract

e18607 Background: FN after myelosuppressive chemotherapy may result in significant morbidity/mortality and increase healthcare costs due to interventions such as hospitalization. For patients receiving chemotherapy at intermediate-risk of FN, guidelines recommend assessing patient-specific FN RFs to decide whether to provide primary prophylaxis. However, there is a paucity of real-world data that quantifies the FN risk based on patient RFs when receiving intermediate-risk chemotherapy. Thus, we examined the association of FN RFs with incident FN in the first and subsequent cycles in patients at intermediate-risk of chemotherapy-induced FN within the real-world. Methods: This retrospective cohort study used the Optum Research Database to identify US commercial and Medicare Advantage patients with a non-myeloid malignancy who were treated between 01 Jan 2009 and 31 Dec 2019 with a first-line intermediate-risk chemotherapy regimen. The following FN RFs were identified based on ICD or procedure codes on claims during the 6 months prior to chemotherapy, unless otherwise stated: radiation, neutropenia, liver dysfunction, renal dysfunction, age > 65 years, metastases to the bone, and surgery during the 30 days prior. FN was defined as ICD codes for neutropenia and fever on a claim. Patients without previous FN were followed for FN from five days after index through the earliest of the following: 1) FN, 2) 31 Dec 2019, 3) death, 4) health plan disenrollment, or 5) end of chemotherapy line or cycle (depending on time frame of interest). Cox regression was used to calculate HRs for incident FN. Results: The study included 13,937 patients, and the most common RFs were 1) recent surgery (84%), 2) age > 65 (67%), and 3) liver dysfunction (31%). Compared to patients with no individual RFs, each additional RF was associated with a greater risk of FN during both the first and subsequent cycles, although confidence intervals were large (Table). Conclusions: Among patients at intermediate-risk of chemotherapy-induced FN, patients with more individual RFs for FN had a higher risk of FN during both the first and all cycles. These results underscore the importance of RF analysis in prophylaxis decisions for patients at intermediate-risk of chemotherapy-induced FN.[Table: see text]