Risks Associated with Chronic Cannabis Use on Opioid Use, Length of Stay, and Revision Rate for Patients Undergoing Posterior Lumbar Interbody Fusion.

BACKGROUND CONTEXT: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.PURPOSE:To investigate the effect of cannabis use on perioperative opioid requirement and revision surgery rate in patients undergoing lumbar fusion.STUDY DESIGN:Retrospective cross-sectional study.PATIENT SAMPLE:A total of 48,499 patients from PearlDiver national database who underwent posterior lumbar interbody fusion.OUTCOME MEASURES: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.