Risk Factors for Prolonged Postoperative Opioid Use After Spinal Fusion for Adolescent Idiopathic Scoliosis.

BACKGROUND: Opioids are commonly used after posterior spinal instrumented fusion (PSIF) for adolescent idiopathic scoliosis (AIS). Prescription opioids use can potentially lead to misuse, abuse, dependence, and overdose death. Prolonged opioid use has not been extensively studied in the postoperative AIS population. The purpose of this study is to identify risk factors associated with prolonged opioid use after PSIF for AIS.

METHODS: A large insurance database was queried for AIS patients undergoing PSIF. Patients with prolonged postoperative opioid use were defined as those receiving new prescriptions for an opioid medication >6 weeks following the date of surgery, up to 8 months postoperatively. Preoperative and intraoperative risk factors for prolonged opioid use were then examined, including the number of spinal levels fused, preoperative opioid prescriptions, demographic variables, pertinent comorbidities (anxiety, depression, attention deficit hyperactivity disorder, and autism) and other preoperative prescriptions (anxiolytics, antidepressants, nonopioid analgesics, neuropathic medications, and attention deficit hyperactivity disorder medications). Each variable's independent risk for prolonged postoperative opioid use was examined utilizing a multivariable binomial regression analysis. P<0.05 was considered statistically significant.

RESULTS: A total of 511 patients were included in the study. Of this 50 patients (9.78%) were found to have prolonged opioid use following scoliosis surgery. Preoperative opioid use (odds ratio, 2.93; P<0.001) was the most significant predictor of prolonged postoperative opioid use. In addition, female sex, obesity, a preoperative diagnosis of anxiety and a preoperative prescription for a muscle relaxer were also significant positive risk factors for prolonged postoperative opioid use. Several factors were found to be protective against prolonged postoperative opioid use. Fewer total fusion levels, compared with ≥13 levels, had a significantly lower risk of prolonged opioid use. Preoperative anxiolytic and antidepressant use were also both negative predictors of prolonged opioid use.

CONCLUSIONS: Efforts at addressing preoperative opioid use, anxiety, obesity, and providing multimodal pain management strategies should be considered to reduce additional postoperative opioid prescriptions after PSIF for AIS.

LEVEL OF EVIDENCE: Level III-retrospective comparative study.