In-patient hospital mortality patterns by day of the week: an analysis of admissions to a regional renal unit

Abstract

Background and aims

Higher mortality rates have been reported for patients admitted at a weekend compared to a weekday. Our aim was to assess in-patient mortality patterns by day of the week, in a tertiary renal unit.

Method and results

Mortality related to day of admission and day of death was analysed over a two-year period at Glasgow Western Infirmary renal unit. Typical caseload was also assessed over two random four-week periods. As a proportion of admissions, 30-day mortality was 46/540 (8.5%) on a weekend day compared with a weekday 107/2013 (5.3%) (RR1.60, p = 0.005). Thirty-day mortality rate was 46/208 = 0.22 deaths/weekend day of admission compared with 107/523 = 0.20 deaths/weekday of admission (incident rate ratio = 1.08, p = 0.67). There was no significant increased risk of death on a weekend day compared to a weekday (RR1.23, p = 0.23). A higher proportion of weekend admissions were from other hospitals. Acute kidney injury and haemodialysis patients formed a higher percentage of admissions.

Conclusion

Admission day mortality expressed as a death rate/day does not differ between weekend/weekday admissions. Admission day mortality expressed as a proportion of total admissions was significantly higher at weekends. This suggests admission case-mix/workload differs at weekends with fewer ‘well’ patients admitted. In-patient mortality patterns are complex and any conclusions made should take into account case mix and workload.