Background:

Opioids are commonly prescribed for chronic pain prior to spinal surgery and research has shown an increased rate of post-operative adverse events in these patients.

Objective:

This study compared the incidence of two-year subsequent surgical procedures and post-operative adverse events in patients undergoing lumbar fusion with or without 90-day pre-operative opioid use. We hypothesized that patients using preoperative opioids to have a higher incidence of subsequent surgery and adverse outcomes.

Methods:

A retrospective cohort study was performed using Optum Pan-Therapeutic Electronic Health Records database including adult patients who had their first lumbar fusion between 2015 and 2018. The daily average preoperative opioid dosage 90 days prior to fusion was determined as morphine equivalent dose (MED) and further categorized into high-dose (MED>100mg/day) and low-dose (1-100mg/day). Clinical outcomes were compared after adjusting for confounders.

Results:

A total of 23,275 patients were included, with 2,112 (10%) patients using opioids preoperatively. There was a significantly higher incidence of infection compared to non-users (12.3% versus 10.1%; P=0.01). There was no association between subsequent fusion surgery (7.9% versus 7.5%, P=0.52) and subsequent decompression surgery (4.1% versus 3.6%; P=0.3) between opioid users and non-users. Regarding post-operative infection risk, low-dose users showed significantly higher incidence (12.7% versus 10.1%; P<0.01), but high-dose users did not demonstrate higher incidence than nonusers (7.5% versus 10.1%; P=0.23).

Conclusion:

Consistent with prior publications, opioid use was significantly associated with a higher incidence of two-year post-operative infection compared to non-use. Low-dose opioid users had higher post-operative infection rates than non-users.