STUDY DESIGN:
Retrospective analysis.

OBJECTIVE:
To investigate gender differences in opioid use after lumbar decompression and fusion surgery for patients with symptomatic lumbar stenosis or spondylolisthesis.

SUMMARY OF BACKGROUND DATA:
Recent studies have demonstrated higher prevalence of chronic pain states and greater pain sensitivity among women compared with men. Furthermore, differences in responsivity to pharmacological and non-pharmacological treatments have been observed. Whether gender differences in perioperative opioid use exists in patients undergoing lumbar fusion for symptomatic stenosis or spondylolisthesis remains unknown.

METHODS:
An insurance database, including private/commercially insured and Medicare Advantage beneficiaries, was queried for patients with symptomatic lumbar stenosis or spondylolisthesis undergoing index 1,2, or 3-level index lumbar decompression and fusion procedures between 2007-2016. Records were searchable by International Classification of diseases diagnosis and procedure codes, and generic drug codes specific to Humana. Opioid use 6-months prior to through 2-years after index surgery was assessed. The primary outcome was gender differences in opioid use after index lumbar surgery. The secondary outcome was independent predictors of prolonged opioid use after lumbar fusion.

RESULTS:
Of the 13,257 participants (females: 7,871, 59.8%), 58.4% of women used opioids compared with 56.9% of men prior to index surgery. At 1-year after surgery, continuous opioid use was observed in 67.1% of women compared to 64.2% of men (p <  0.001). Within 2-years post-operatively, opioid use was observed in 83.1% of women versus 82.5% men. In a multivariate logistic regression analysis, female gender (OR 1.14, 95% CI:1.058-1.237), obesity (OR 1.10, 95% CI:1.004-1.212), and pre-operative narcotic use (OR 3.43, 95% CI:3.179-3.708) was independently associated with prolonged (>1year) opioid use after index surgery.

CONCLUSIONS:
We observed a higher prevalence of chronic opioid use among women following lumbar fusion surgery. Female sex was independently associated with prolonged opioid use after index surgery.

LEVEL OF EVIDENCE:
3.