Risks associated with chronic cannabis use on opioid use, length of stay, and revision rate for patients undergoing posterior lumbar interbody fusion.

Background: Opioids are commonly prescribed to treat spinal pain, especially those undergoing surgery. Cannabis has been suggested as an agent that can modulate opioid needs in these patients.

Objective: To investigate the effect of cannabis use on perioperative opioid requirement and revision surgery rate in patients undergoing lumbar fusion.

Methods: Retrospective cross-sectional study. Methods: A total of 48,499 patients from PearlDiver national database who underwent posterior lumbar interbody fusion. Methods: Opioid-use rates, MME, length of stay, and revision rates. Methods: Using PearlDiver, we identified patients for posterior lumbar interbody fusion (PLIF), cannabis use disorder, revision lumbar fusion, demographics, and comorbidities. Cannabis users and non-users were propensity matched for age, sex, and tobacco use. Pre and postoperative cumulative morphine milli equivalence (MME) were calculated. Opioid-use rates, MME, length of stay (LOS), and revision rates were compared using univariate analysis. Revision rates were compared using Kaplan-Meyer log-rank analysis, and logistic and cox regression.

Results: Of 48,499 patients undergoing PLIF, 3.4% were identified as chronic cannabis users. They were younger, and more likely to be male and use tobacco. They had a higher rate and amount of opioid use within 90-days preoperatively, and 90- and 365-days postoperatively, after controlling for age, sex, and tobacco use. Cannabis users had longer LOS (4.4 vs 4.0 days), and a higher rate of revision surgery (6.9% vs 3.2%). Log-rank analysis, as well as logistic and cox regression confirmed an increased revision rate. Concurrent tobacco and cannabis use also had an additive effect on revision rate to 8.1%, compared with those who used only cannabis (5.4%) or tobacco (4.5%).

Conclusions: Chronic cannabis use is associated with an increased preoperative and long-term postoperative opioid use, a longer length of stay, and an increased revision rate.