Demand for emergency department services in the elderly: an 11 year analysis of the Greater Sydney Area.

Objective: To describe trends in population-based rates of ED presentations in the Greater Sydney Area (GSA) and compare these between the elderly and non-elderly age groups.

Methods: This was a retrospective study using ED presentation data from all public hospitals in the GSA and population data from the Australian Bureau of Statistics between 2001 and 2011. Age-specific ED presentation rates stratified by age group (<65 years, 65-79 years and ≥80 years of age) were presented and compared using negative binomial regression and generalised linear regression models.

Results: Over 11 million ED presentations were analysed. The annualised rate of increase in ED presentations per 1000 population was 1.8% per annum. The adjusted incidence rate ratio for patients aged 80 years and over was 3.6 times higher than patients younger than 65 years (95% CI 2.8, 4.7, P < 0.001) and 1.6 times higher for patients between 65 and 79 years of age (95% CI 1.4, 1.8, P < 0.001). There was an increase of 40 patients per 1000 population per year admitted to hospital from ED (β = 40, 95% CI 29, 52 P < 0.001) in patients aged 80 years or older compared with those aged less than 65 years of age.

Conclusions: A disproportionate increase in ED presentation rates and in-patient admission rates in patients aged 80 years and over was demonstrated over 11 years in the GSA. ED models of care and system wide strategies to address these demographic changes are required.