Socioeconomic determinants of very frequent presentations to emergency departments in New South Wales, Australia: A state wide data linkage study.

Objectives: To describe the clinical and longitudinal patterns of presentation, and to understand the underlying socioeconomic characteristics of different modes of presentation.

Design: Retrospective state-wide data linkage analysis of emergency department (ED) presentations. Patients were included if they were 18 years of age or over and presented to the ED over twenty times within any consecutive 365-day period between January 2015 and December 2020. This analysis used routinely collected data from the Emergency Department Data Collection and Admitted Patient Data Collection. The quintile of Socioeconomic Indexes for Area (SEIFA) defined by Australian Bureau of Statistics was used for equity considerations.

Main Outcome Measures: The main outcomes of interest included patients' clinical presentation, demographic information and SEIFA score as represented by Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD) quintiles.

Results: There were 417,154 presentations and 5,244 patients who met the inclusion criteria. The majority of the presentations were from SEIFA groups 1 (28.2 %) and 2 (35.6 %). The most common presentations were for drug and alcohol (17.5 %), followed by abdominal pathology (11.8 %) and mental health (11.5 %). In the lowest SEIFA group, the main presenting complaints were for drug and alcohol and administrative presentations. While in the highest SEIFA group, the main presentations were for mental health then abdominal pain, followed by drug and alcohol presentations.

Conclusion: Patients in the lower SEIFA groups tended to be older with lower acuity presentations and were more likely to present to the same facility, more regularly. Patients in the lower SEIFA group were also more likely to present with drug and alcohol and administrative presentations while those in the higher SEIFA groups were more likely to present with mental health presentations. System wide interventions are needed to address the needs of both groups, particularly those from lower socioeconomic backgrounds, who would benefit from improved access to primary care either through access to General Practice or Urgent Care Centres.