Cannabis Abuse and Perioperative Complications Following Inpatient Spine Surgery in the United States.

STUDY DESIGN Retrospective cohort analysis of a nationwide administrative database. OBJECTIVE To analyze the association between cannabis abuse and serious adverse events following elective spine surgery. SUMMARY OF BACKGROUND DATA Cannabis is the most popular illicit drug in the United States, and its use has been increasing in light of state efforts to decriminalize and legalize its use for both medical and recreational purposes. Its legal status has long precluded extensive research into its adverse effects, and to date, little research has been done on the sequelae of cannabis on surgical patients, particularly in spine surgery. METHODS The 2012-2015 Nationwide Inpatient Sample was queried for all patients undergoing common elective spine surgery procedures. These patients were then grouped by the presence of concurrent diagnosis of cannabis use disorder and compared with respect to various peri- and postoperative complications, all-cause mortality, discharge disposition, length of stay, and hospitalization costs. Propensity score matching was utilized to control for potential baseline confounders. RESULTS A total of 423,978 patients met inclusion/exclusion criteria, 2,393 (0.56%) of whom had cannabis use disorder. After controlling for baseline characteristics and comorbid tobacco use, these patients similar inpatient mortality, but higher rates of perioperative thromboembolism (OR 2.2; 95% CI 1.2 to 4.0; p = 0.005), respiratory complications (OR 2.0; 95% CI 1.4 to 2.9; p < 0.001), neurologic complications such as stroke and anoxic brain injury (OR 2.9; 95% CI 1.2 to 7.5; p = 0.007), septicemia/sepsis (OR 1.5; 95% CI 1.0 to 2.5; p = 0.031), and non-routine discharge (p < 0.001), as well as increased lengths of stay (7.1 vs. 5.2 days, p < 0.001) and hospitalization charges ($137,631.30 vs. $116,112.60, p < 0.001). CONCLUSIONS Cannabis abuse appears to be associated with increased perioperative morbidity among spine surgery patients. Physicians should ensure that a thorough preoperative drug use history is taken, and that affected patients be adequately informed of associated risks.Level of Evidence: 3.