Outcome of elderly emergency department patients hospitalised on weekends: a retrospective cohort study

Background: Studies investigating different medical conditions and settings have demonstrated mixed results regarding the weekend effect. However, data on the outcome of elderly patients hospitalised on weekends is scarce. The objective was to compare in-hospital and two-day mortality rates between elderly emergency department (ED) patients (>= 65 years) admitted on weekends versus weekdays. Methods: A retrospective cohort study of emergency department visits of internal medicine patients >= 65 years presenting to the emergency department between 01 and 09-2010 and 31-08-2012 was conducted. The weekend was defined as the period from midnight on Friday to midnight on Sunday. Results: Data on 3697 emergency department visits by elderly internal medicine patients (mean age 78.6 years old) were included. In total, 2743 emergency department visits (74.2%) resulted in hospitalisation, of which 22.9% occurred on weekends. Comorbidity and urgency levels were higher in patients admitted on weekends. In-hospital mortality was 11.4% for patients admitted on weekends compared with 8.9% on weekdays (OR 1.3, 95% CI 0.99-1.8). Two-day mortality was 3.2% in patients hospitalised on weekends versus 1.9% on weekdays (OR 1.7, 95% CI 0.99-2.9). Multivariable adjustment for age, comorbidity and triage level demonstrated comparable in-hospital and two-day mortality for weekend and week admission (ORadj 1.2, 95% CI 0.9-1.7 and ORadj 1.5, 95% CI 0.8-2.6, resp.). Conclusion: A small weekend effect was observed in elderly internal medicine patients, which was not statistically significant. This effect was partly explained by a higher comorbidity and urgency level in elderly patients hospitalised on weekends than during weekdays. Emergency care for the elderly is not compromised by adjusted logistics during the weekend.