Predictors of Long-term Opioid Use Following Lumbar Fusion Surgery

Study Design. A population-based retrospective cohort study. Objective. The aim of this study was to examine risk factors for long-term opioid use following lumbar spinal fusion surgery in a nationally representative cohort of commercially insured adults. Summary of Background Data. Opioid prescription rates for the management of low back pain have more than doubled in the US over the past decade. Although opioids are commonly used for the management of pain following lumbar spinal fusion surgery, to date, no large-scale nationally representative studies have examined the risk factors for long-term opioid use following such surgical intervention. Methods. Using one of the nation's largest commercial insurance databases, we conducted a retrospective cohort study of 8377 adults, aged 21 to 63 years, who underwent lumbar spinal fusion surgery between January 1, 2009, and December 31, 2012. Long-term opioid use was defined as >= 365 days of filled opioid prescriptions in the 24 months following lumbar fusion. Multivariable logistic regression was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals for the risk of long-term opioid use following lumbar fusion. Results. After adjusting for covariates, the following factors were associated with an increased risk of long-term opioid use following surgery: duration of opioid use in the year before lumbar surgery [Referent (0 days); Quartile 1 (1-22 days) OR = 2.27, 95% CI = 1.48-3.49; Quartile 2 (23-72 days): OR = 5.94, 95% CI = 4.00-8.83; Quartile 3: (73-250 days) OR = 25.31, 95% CI = 17.26-37.10; Quartile 4 (>= 250 days) OR = 219.95, 95% CI = 148.53-325.71)], refusion surgery (OR = 1.32, 95% CI = 1.02-1.72), and diagnosis of depression (OR = 1.43, 95% CI =1.18-1.74). Receipt of anterior fusion was associated with a modest decrease in the risk of long-term opioid use (OR = 0.79, 95% CI = 0.63-0.99). Conclusion. These findings may provide clinically relevant information to physicians, patients, and their families regarding the risk factors for opioid dependence following lumbar fusion surgery.