Friday and weekend hospital stays: effects on mortality

While weekend hospital admissions are associated with higher mortality, the effects of weekend hospital stays are not known. We assessed whether patients hospitalised for chronic obstructive pulmonary disease (COPD) or pneumonia have higher mortality during weekend and Friday stays. Our cohort consisted of all hospitalisations for COPD or pneumonia during 1990-2007 from the healthcare databases of the province of Quebec, Canada. The hazard ratio (HR) of in-patient death associated with Friday and weekend stay was estimated by the Cox model with time-dependent covariates, adjusted for age, sex and comorbidity. The cohort included 323 895 hospitalisations for COPD or pneumonia during which 32 414 deaths occurred (rate of death 8.06 per 1000 per day). Mortality was higher for weekend (HR 1.06, 95% CI 1.03-1.09) but not Friday admissions (HR 0.97, 95% CI 0.95-1.00), relative to Monday-Thursday admissions. Independently of the admission day, mortality was higher during weekend stays (HR 1.07, 95% CI 1.04-1.09) and Friday stays (HR 1.05, 95% CI 1.02-1.08), relative to Monday-Thursday stays. Patients hospitalised for COPD or pneumonia are at increased risk of death when staying over on a Friday or a weekend. The additional 40-56 deaths per 100 000 patients staying in hospital on those days are most likely due to reduced access to healthcare at that time.