Using network analyses to characterise Australian and Canadian frequent attenders to the emergency department

ObjectiveResults To explore and compare the characteristics of frequent attenders to the ED at an Australian and a Canadian tertiary hospitals by utilising a network analysis approach. Methods We conducted a retrospective population-based study using administrative data over the 2018 and 2019 calendar years. Participants were from a tertiary hospital in Melbourne, Australia, and Toronto, Canada. Frequent attenders were defined as patients with four or more visits in 12 months. Characteristics of younger (18-39 years), middle-aged (40-69 years) and older (70 years and older) frequent attenders were described using descriptive statistics and network analyses. Younger frequent attenders were characterised by mental illness and substance use, while older frequent attenders had high rates of physical (including chronic) diseases. Middle-aged frequent attenders were characterised by a combination of mental and physical illnesses. These findings were observed at both hospitals. Across all age groups, the network analyses between the Melbourne and Toronto hospitals were different. Among older frequent attender visits, more diagnoses were associated with high triage acuity at the Toronto hospital than at the Melbourne hospital. Some associations were similar at both sites, for example, the negative correlation between high triage acuity and joint pain. Conclusion Younger, middle-aged and older frequent attenders have distinct characteristics, made readily apparent by using network analyses. Future interventions to reduce ED visits should consider the heterogeneity of frequent attenders who have needs specific to their age, presenting problems and jurisdiction.