347 Short-Term Pain Outcomes and Pain Medication Utilization Among Urine Toxicology-Identified Opioid and Marijuana Users Following Elective Spine Surgery

INTRODUCTION: Postoperative pain outcomes may be influenced by preoperative substance use, which is often underreported due to associated stigma. METHODS: Patients undergoing elective spinal surgery between September 2020 and May 2022 were recruited for this prospective cohort study. Detailed chart review was completed to collect demographic, urine toxicology, VAS, and pain medication regimen data. Comparisons between self-reported and urine toxicology-identified substance use, pre- and post-operative VAS ratings, and postoperative pain medication use were made using χ2 tests, student’s t-tests, and logistic regression, respectively. Models were adjusted for age, sex, and race. RESULTS: Among 111 participants (mean age 58 years, 59% female, 95% with >1 comorbidity), urine toxicology overestimated drug use (47% vs 16%, p < 0.001) and underestimated alcohol use (16% vs 56%, p < 0.001) at preoperative baseline relative to patient reports. Two-weeks postoperatively, participants on preoperative opioids as determined by urine toxicology reported no significant improvements in pain from baseline (6.67 preop vs 5.92 postop, p = 0.288) unlike non-users (6.56 preop vs 4.61 postop, p < 0.001). They also had worse postoperative VAS (5.92 vs 4.61, p = 0.030) and heavier reliance on opioid medications (OR = 3.09, 95% CI = 1.21-7.89, p = 0.019). Conversely, participants on preoperative marijuana reported similar improvements in pain from baseline (users: 6.88 preop vs 4.36 postop, p = 0.001; non-users: 6.49 preop vs 5.07 postop, p = 0.001), similar postoperative pain (4.36 vs 5.07, p = 0.238), and similar postoperative reliance on opioid medications (OR = 0.96, 95% CI = 0.38-2.44, p = 0.928). CONCLUSIONS: While urine toxicology-identified preoperative opioid use was associated with poor postoperative pain relief and continued reliance on postoperative opioids for pain management following elective spinal surgery, preoperative marijuana use was not. Preoperative marijuana use, hence, should not delay or be a contraindication to elective spinal surgery.