Primary Care use during, and Wait Times to Receiving, Adjuvant Breast Cancer Chemotherapy: A Population-based Retrospective Cohort Study using CanIMPACT Data

OBJECTIVES: To determine how physical and/or mental comorbidities affect primary care physician (PCP) use during adjuvant breast cancer chemotherapy and how PCP continuity affects time to chemotherapy. METHODS: Population-based, retrospective cohort study of 12,781 women diagnosed with stage I-III breast cancer in Ontario who received adjuvant chemotherapy. RESULTS: Six-month PCP visit rate increased during chemotherapy (mean 2.3 baseline visits, 3.4 chemotherapy visits). Low physical/mental comorbidity patients saw larger increases (1.4/1.8 baseline, 2.8/3.0 chemotherapy) versus high physical/mental comorbidity (5.6/3.5 baseline, 5.3/4.1 chemotherapy). Median time to chemotherapy (126 days) was shorter by 3.21 days in symptom-diagnosed patients with low PCP continuity, 17.43 days in screen-diagnosed immigrants with high PCP continuity and 10.68 days in symptom-diagnosed patients with no baseline PCP utilization. CONCLUSIONS: Patients with low physical and/or mental comorbidity showed greater increases in PCP use during adjuvant chemotherapy. Higher PCP continuity was associated with shorter median time to chemotherapy in screen-diagnosed immigrants.M.Sc