Are Emergency Departments becoming inaccessible for vulnerable groups of patients? A retrospective cohort study

Background Emergency Department (ED) overcrowding is associated with adverse outcomes including delays to treatment, patients leaving without being seen and increased mortality. Increasingly, evidence suggests that crowding may disproportionately affect those of lower socioeconomic status, worsening health inequalities. This study investigates the relationship between prolonged ED length of stay and vulnerable patient groups choosing not to wait to be seen. Methods A retrospective cohort study analysed monthly ED attendance data from a large district general hospital between January 2020 and July 2025. Patients who did not wait to be seen (DNW) were assessed for vulnerability based on age, presenting complaint and inferred frailty. Associations were explored using generalised estimation equation model with binary outcome. Results During the 66-month study period, 317,978 patients attended the ED, of whom 35,403 (11.1%) did not wait to be seen. Of these, just under one third met vulnerability criteria. As the percentage of patients staying in the ED for more than 8-hours increased, so did the proportion of patients leaving the department without being seen. With each 10% increase in LOS>8h percentage, the odds of any patient choosing not to wait increases by 48% (OR=1.48, 95% CI(1.47 to 1.49), p<0.001). Of the three vulnerability groups assessed, paediatric patients, those presenting with mental health complaints and frailty, frail patients were the most affected when lengths of stay in the ED increased and crowding became a problem (OR=1.73, 95% CI(1.72 to 1.74), p<0.001). Conclusion These findings demonstrate that while all patient groups are more likely to leave without being seen as crowding worsens, elderly and paediatric patient cohorts are significantly more likely to leave without being seen as crowding worsens. This raises genuine concerns about the accessibility of healthcare, in the presence of crowding, in these vulnerable groups.