Cannabis Use Disorder and Perioperative Outcomes in Major Elective Surgeries: A Retrospective Cohort Analysis
Akash Goel, M.D., M.P.H.; Brandon McGuinness, M.D.; Naheed K. Jivraj, M.B.B.S., M.Sc.; Duminda N. Wijeysundera, M.D., Ph.D.; Murray A. Mittleman, M.D., Dr.P.H.; et alBrian T. Bateman, M.D., M.Sc.; Hance Clarke, M.D., Ph.D.; Lakshmi P. Kotra, B.Pharm. (Hons), Ph.D.; Karim S. Ladha, M.D., M.Sc.
 Author Notes
From the Department of Anesthesiology, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada (A.G., N.K.J., H.C.); Harvard T. H. Chan School of Public Health, Boston, Massachusetts (A.G., B.M., M.A.M.); Division of Vascular Surgery, McMaster University, Hamilton, Ontario, Canada (B.M.); Department of Anesthesia and Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada (N.K.J., D.N.W., K.S.L.); Department of Anesthesia and Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario, Canada (D.N.W., K.S.L.); Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts (M.A.M.); Department of Anesthesiology, Perioperative and Pain Medicine, and Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts (B.T.B.); Leslie Dan Faculty of Pharmacy, University of Toronto, and Krembil Research Institute, University Health Network, Toronto, Ontario, Canada (L.P.K.).
Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
A.G. and B.M. contributed equally to this article.
Submitted for publication April 11, 2019. Accepted for publication October 25, 2019.
Correspondence: Address correspondence to Dr. Ladha: Department of Anesthesia, St. Michael’s Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada. karim.ladha@mail.utoronto.ca. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Anesthesiology Newly Published on November 25, 2019. doi:https://doi.org/10.1097/ALN.0000000000003067

Abstract
Editor’s Perspective:

What We Already Know about This Topic:

Cannabis is known to have cardiovascular and psychoactive effects

The association between active cannabis use disorder and postoperative outcomes remains unclear

What This Manuscript Tells Us That Is New:

In the United States, administrative data demonstrate that cannabis use disorder has increased in prevalence from 2010 to 2015

Active cannabis use disorder is not associated with a change in overall perioperative morbidity, mortality, length of stay, or costs

However, active cannabis use disorder is associated with a meaningful increase in the risk of postoperative myocardial infarction

Background: Although cannabis is known to have cardiovascular and psychoactive effects, the implications of its use before surgery are currently unknown. The objective of the present study was to determine whether patients with an active cannabis use disorder have an elevated risk of postoperative complications.

Methods: The authors conducted a retrospective population-based cohort study of patients undergoing elective surgery in the United States using the Nationwide Inpatient Sample from 2006 to 2015. A sample of 4,186,622 inpatients 18 to 65 yr of age presenting for 1 of 11 elective surgeries including total knee replacement, total hip replacement, coronary artery bypass graft, caesarian section, cholecystectomy, colectomy, hysterectomy, breast surgery, hernia repair, laminectomy, and other spine surgeries was selected. The principal exposure was an active cannabis use disorder, as defined by International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) diagnostic codes for cannabis dependence and cannabis abuse. The primary outcome was a composite endpoint of in-hospital postoperative myocardial infarction, stroke, sepsis, deep vein thrombosis, pulmonary embolus, acute kidney injury requiring dialysis, respiratory failure, and in-hospital mortality. Secondary outcomes included hospital length of stay, total hospital costs, and the individual components of the composite endpoint.

Results: The propensity-score matched-pairs cohort consisted of 27,206 patients. There was no statistically significant difference between patients with (400 of 13,603; 2.9%) and without (415 of 13,603; 3.1%) a reported active cannabis use disorder with regard to the composite perioperative outcome (unadjusted odds ratio = 1.29; 95% CI, 1.17 to 1.42; P < 0.001; Adjusted odds ratio = 0.97; 95% CI, 0.84 to 1.11; P = 0.63). However, the adjusted odds of postoperative myocardial infarction was 1.88 (95% CI, 1.31 to 2.69; P < 0.001) times higher for patients with a reported active cannabis use disorder (89 of 13,603; 0.7%) compared with those without (46 of 13,603; 0.3%) an active cannabis use disorder (unadjusted odds ratio = 2.88; 95% CI, 2.34 to 3.55; P < 0.001).

Conclusions: An active cannabis use disorder is associated with an increased perioperative risk of myocardial infarction.