Effect of Access to After-Hours Primary Care on the Association Between Home Nursing Visits and Same-Day Emergency Department Use

PURPOSE: Previous work has demonstrated that home care patients have an increased risk of visiting the emergency department after a home nursing visit on the same day. We investigated whether this association is modified by greater access to after-hours primary care. METHODS: We conducted a population-based case-crossover study of home care patients in Ontario, Canada in 2014-2016. Emergency department visits after 5:00 pm were selected as case periods and matched, within the same patient, to control periods within the previous week. The association between home nursing visits and same-day emergency department visits was estimated with conditional logistic regression. Access to after-hours primary care, measured on the patient and practice level, was tested for effect modification using an interaction term approach. Analysis was performed separately for all emergency department visits and a less urgent subset not admitted to hospital. RESULTS: A total of 11,840 patients contributed cases to the analysis. Patients with a history of after-hours primary care use had a smaller increased risk of a same-day after-hours emergency department visit (OR = 1.18; 95% CI, 1.06-1.30) compared with patients with no after-hours care (OR = 1.31; 95% CI, 1.25-1.39). The modifying effect was stronger among emergency department visits not admitted to hospital (OR = 1.11; 95% CI, 0.97-1.28 vs OR = 1.41; 95% CI, 1.31-1.51). CONCLUSION: Greater access to after-hours primary care reduced the risk of less-urgent emergency department use associated with home nursing visits. These findings suggest increasing access to after-hours primary care could prevent some less-urgent emergency department visits.