Study: Weekend effect raises risk of surgical patient mortality, complications

Editor's Note

A March 4 study in JAMA Network Open underscores the persistence of the “weekend effect,” a surgical care phenomenon in which the risk of postoperative complications, readmissions and mortality rises immediately before the weekend. The research suggests variations in staffing, resource availability, and care coordination may contribute to worse outcomes.

The retrospective analysis included 429,691 adult patients in Ontario, Canada, who underwent one of 25 common surgical procedures between 2007 and 2019. The study compared outcomes for patients who had surgery the day before the weekend (typically Friday) with those who had surgery the day after (typically Monday). Key findings include:

• Patients in the preweekend group were significantly more likely to experience the composite outcome of death, complications, and readmissions at 30 days (adjusted odds ratio [aOR] 1.05, 95% CI 1.02-1.08), 90 days (aOR 1.06, 95% CI 1.03-1.09), and 1 year (aOR 1.05, 95% CI 1.02-1.09).
• The odds of death were higher for patients undergoing surgery before the weekend at 30 days (aOR 1.09, 95% CI 1.03-1.16), 90 days (aOR 1.10, 95% CI 1.03-1.17), and 1 year (aOR 1.12, 95% CI 1.08-1.17).
• Preweekend surgery was associated with an increased length of hospital stay (adjusted relative risk 1.06, 95% CI 1.04-1.08).

Subgroup analysis revealed that elective procedures performed before the weekend were associated with worse outcomes, while emergent surgeries showed slightly better outcomes when performed before the weekend. The latter finding may be due to delays in emergency care over the weekend, leading to worse outcomes when surgeries are deferred until Monday, researchers write.

Although consistent with other published research, “this study is novel in that it comprehensively analyzes the weekend effect on perioperative outcomes, including all surgical specialties, encompassing both emergent and nonemergent surgical procedures, and analyzing short-term (30-day), intermediate (90-day), and long-term (1-year) outcomes,” researchers write. Potential strategies to mitigate the weekend effect include optimizing staffing models, improving adherence to postoperative protocols, and enhancing weekend care coordination.