101 - Opioid Cessation and Post-Operative Complications Among Posterior Lumbar Interbody Fusion Patients on Pre-Operative Methadone

Introduction:

Pre-operative opioid use is associated with greater post-operative opioid use. Long-term opioid use is associated with poorer outcomes and increased adverse effects. Little research has evaluated post-operative opioid consumption among populations taking methadone, a synthetic opioid used in medication-assisted treatment for opioid use disorder. In this study, we examined the reduction in post-operative opioid use among patients taking methadone following posterior lumbar interbody fusion (PLIF), as well as medical complications and need for additional lumbar surgery, compared with other opioid users and nonusers.

Methods:

Patients who underwent PLIF from 2016 to 2019 were identified using the PearlDiver database and grouped by their use of methadone, any opioid(s), or no opioid within 90 days before the index surgery. Post-operative opioid prescriptions were tracked for two years. Those who stopped opioid use by 90 days after surgery were classified as LOW users. Those who continued post-operative opioid use after 365 days were HIGH users. Medical complications within 30 days after surgery, deep infection, 90-day readmission rates, and need for additional lumbar surgery after the index surgery were compared. Groups were compared using ANOVA for continuous and chi-squared for discrete variables. Log rank tests on survival curves were done to compare the revision rates.

Results:

56,734 total PLIF patients were identified. 978 patients received methadone, 48,498 took other opioid(s), and 8,139 had no opioid use 90 days before surgery. Mean ages were 52.7 ± 10.0, 56.4 ± 11.6, 63,4 ± 11.8 for the three groups, respectively (p < 0.0001). 16.4%, 37.2%, and 79.5% of the patients in the methadone, opioid, and no opioid groups, respectively, were classified as LOW users (p < 0.0001), 72.8%, 48.7%, and 15.7% were HIGH users (p < 0.0001). Odds ratio of being a HIGH user compared to other opioid use or nonuser before the surgery was 2.96 and 17.0. Medical complication rates within 30 days were 4.4%, 3.1%, and 2.5%, respectively (p < 0.001). Deep infections occurred in 3.5%, 2.0%, and 1.1% (p < 0.0001).Additional lumbar surgeries were performed in 5.4%, 3.7%, and 2.4% (P < 0.001). Log rank test on a survival curve compared to other opioid users and non-users showed a statistically higher revision rate (p = 0.008, p < 0.0001, respectively).

Conclusion:

This work confirms previous findings that pre-operative opioid use is strongly predictive of post-operative opioid use, and indicate that patients taking methadone pre-operatively are unlikely to stop opioid use one year after PLIF. Pre-operative opioid use has been identified as being associated with increased re-operations, surgical site infection, post-operative healthcare utilization, post-operative length of stay, and as a risk factor for development of chronic post-operative opioid use among patients undergoing spine surgery. Our work indicates that, when compared with the non-methadone opioid group and the no-opioid group, patients taking methadone have significantly higher rates of infection, medical complications, and additional surgery compared to non-methadone opioid users and non-opioid users. These findings indicate increased costs to the patient and healthcare system and increased risk of adverse outcomes. These risks should be considered in discussions with patients and as a component of their care by providers.