Importance: Cannabis use is growing in the US and is increasingly perceived as harmless. However, the perioperative impact of cannabis use remains uncertain.

Question: Is cannabis use disorder associated with an increased risk of perioperative complications and in-hospital mortality after major elective inpatient surgery?

Findings: In this cohort study that analyzed 12 422 hospitalizations after major elective, noncardiac surgery from the 2016-2019 National Inpatient Sample database, cannabis use disorder was associated with an increased risk of composite perioperative complications and mortality. The outcome occurred more frequently in the group with cannabis use disorder (7.73%) than in the unexposed group (6.57%).

Meaning: This study’s findings suggest that cannabis use disorder is associated with increased risk of patient morbidity and in-hospital mortality after major elective, inpatient, noncardiac surgery.