Impact of socioeconomic status on presentation, care quality and outcomes of patients attended by emergency medical services for dyspnoea: a population-based cohort study

Background Low socioeconomic status (SES) has been linked to poor outcomes in many conditions. It is unknown whether these disparities extend to individuals presenting with dyspnoea. We aimed to evaluate the relationship between SES and incidence, care quality and outcomes among patients attended by emergency medical services (EMS) for dyspnoea. Methods This population-based cohort study included consecutive patients attended by EMS for dyspnoea between 1 January 2015 and 30 June 2019 in Victoria, Australia. Data were obtained from individually linked ambulance, hospital and mortality datasets. Patients were stratified into SES quintiles using a composite census-derived index. Results A total of 262 412 patients were included. There was a stepwise increase in the age-adjusted incidence of EMS attendance for dyspnoea with increasing socioeconomic disadvantage (lowest SES quintile 2269 versus highest quintile 889 per 100 000 person years, p(trend)<0.001). Patients of lower SES were younger and more comorbid, more likely to be from regional Victoria or of Aboriginal or Torres Strait Islander heritage and had higher rates of respiratory distress. Despite this, lower SES groups were less frequently assigned a high acuity EMS transport or emergency department (ED) triage category and less frequently transported to tertiary centres or hospitals with intensive care unit facilities. In multivariable models, lower SES was independently associated with lower acuity EMS and ED triage, ED length of stay>4 hours and increased 30-day EMS reattendance and mortality. Conclusion Lower SES was associated with a higher incidence of EMS attendances for dyspnoea and disparities in several metrics of care and clinical outcomes.