Authors: Pauls LA et al. J Hosp Med 2017 Sep .
Meta-analysis of observational studies showed nearly 20% higher mortality for weekend admissions.
Whether mortality is more likely after weekend hospital admissions than after weekday admissions is unclear. In a meta-analysis of 97 observational studies, researchers evaluated worldwide data on >51 million inpatients for in-hospital, 7-day, or 30-day mortality; admissions were categorized as weekend or weekday.
Patients admitted on weekends had significantly higher mortality at 30 days than did patients admitted on weekdays (4.3% vs. 3.6%), but substantial study heterogeneity was noted. Prespecified subgroup analyses did not demonstrate a link between excess mortality associated with weekend admissions and any hospital or patient factors that differed between weekday and weekend admissions — including hospital staffing, patients’ illness severity, rates of procedure interventions, or time delay to interventions.
Despite this meta-analysis’s shortcomings — varying measures of mortality (in-hospital vs. 7-day or 30-day), variable definitions of “weekend,” and substantial heterogeneity between studies — the association between weekend hospital admissions, compared with weekday hospital admissions, and mortality was impressive. Factors contributing to this “weekend effect” could not be delineated clearly in this investigation and could be related to selection bias; however, further investigation could define whether changes in processes of care or infrastructure (e.g., improving weekend procedure capabilities, raising weekend staffing levels) would lower weekend mortality effectively.