Unwarranted variation in time to initiation of adjuvant chemotherapy in a statewide collaborative.

264 Background: The purpose of this study was to investigate clinical and non-clinical factors associated with time to initiation of breast cancer adjuvant chemotherapy following the final definitive surgery in a state-wide collaborative.

METHODS: We collected prospective data from all patients who received adjuvant chemotherapy for Stages I - III breast cancer in 25 health systems in the Michigan Breast Oncology Quality Initiative (MiBOQI) between 2006 - 2014. MiBOQI is a Blue Cross Blue Shield of Michigan/Blue Care Network-sponsored quality collaborative. The dependent variable was time to initiation of adjuvant chemotherapy. Time to chemotherapy was examined according to clinical and non-clinical patient and treatment factors and by health system, both with and without adjustment for patient and treatment variables.

RESULTS: Complete data were available for 7,513 of 8,236 eligible (91%) patients. The mean time to chemotherapy was 43 days (range 5-390). In multivariate analyses, clinical factors independently associated with longer time to chemotherapy included increasing age, greater comorbidity, and obesity (p value < 0.0001 for all). Higher stage disease was associated with shorter time to chemotherapy (p < 0.0001); there was no association with hormone receptor or HER2 status. Treatment factors associated with longer time to chemotherapy were breast reconstruction, receipt of genomic assays, and receipt of advanced imaging (p value < 0.0001 for all). Non-clinical factors-minority status, higher area-level poverty, and non-private insurance-were also independently associated with longer time to chemotherapy (p value < 0.0001 for all). In addition, time to chemotherapy varied significantly between health system (p < 0.0001); this difference persisted after adjustment for all patient and treatment factors.

CONCLUSIONS: Clinical and non-clinical factors, including site of care, are associated with variation in time to initiation of chemotherapy. Identifying patient-level factors and processes of care that facilitate or impede timely initiation of chemotherapy may decrease unwarranted variation in care delivery across a collaborative network.