Outcomes after emergency department use in patients with cancer receiving chemotherapy in Ontario, Canada: a population-based cohort study

Background — Patients with cancer frequently require emergency medical care during treatment. The objective of this study was to characterize emergency department visits made by patients with cancer receiving chemotherapy and to describe associated outcomes.

Methods — This retrospective cohort study used population-based administrative data from Ontario, Canada. Patients aged 18 years and older, with a cancer diagnosis, and who received chemotherapy in the 30 days before being seen in an emergency department between 2013 and 2017 were included. Emergency department discharge diagnosis codes were categorized to identify the most frequent emergency department diagnoses. We examined the proportion of patients admitted to hospital and 30-day mortality. We used logistic regression to identify predictors of hospital admission.

Results — We identified 218 459 emergency department visits made by 87 555 patients. The median number of emergency department visits per patient was 2 (interquartile range 1–3). Hematological, gastrointestinal, breast and lung cancer were the most common malignancies represented. The most common emergency department diagnoses were infection or fever (57 036 [26.1%]) and gastrointestinal diagnoses (26 456 [12.2%]). Of all visits, 77 978 (35.7%) resulted in admission to hospital. Thirty-day mortality after an emergency department visit was 9.8%. There was an increased odds of admission among patients who previously received palliative consultation, patients with bone or soft tissue or hematological malignancies, and patients with infection, gastrointestinal, pulmonary, cardiac, weakness or genitourinary and nephrology diagnoses.

Interpretation — Patients with cancer frequently used the emergency department during chemotherapy, and 1 in 4 emergency department visits were for infection or fever. These results highlight opportunities to optimize care for certain patients being actively treated for cancer, particularly around infectious complaints.