ASSESSMENT OF CHANGES IN OPIOID UTILIZATION ONE YEAR AFTER ELECTIVE SPINE SURGERY: A CANADIAN SPINE OUTCOMES AND RESEARCH NETWORK STUDY

Chronic opioid use has been associated with negative individual and societal consequences. Our primary objective was to identify perioperative changes in opioid use amongst patients undergoing elective spinal surgery. Our secondary objective was to assess baseline and perioperative factors associated with positive or negative change in opioid use at one-year post surgery. A retrospective review of CSORN data (patient reported measures, socio-demographic factors, lifestyle factors and perioperative procedural information) was performed. Multivariable logistic regression models were used to examine the associations between these factors and change in opioid use. Our data included 5059 patients (2628 (51.9%)-non-users/2431(48.1%)-users) with opioid change data, of which 52.7% were male. At one-year postoperative, 77.5% of patients were not using opioids. Patients were stratified into the following subgroups based on change in baseline opioid use status: (a) non-users-no-change (47.4%), (b) users-no-change (17.9%), (c) non-user-changed to users (4.5%), and (d) user-changed to non-user (30.1%). In other words, 62.7% of baseline users became non-users and 8.7% of non-users became users at one-year. The following baseline factors were independently associated with 1) opioid users who became non-users: lower BMI, fewer comorbidities, non-smoker, not living alone, no insurance claims, routinely exercising, shorter operations, spondylolisthesis diagnosis; 2) opioid users who remained users: higher BMI, more comorbidities, cervical spine location, smoking, married, living alone, compensation claims, not working, no routine exercise, higher PHQ9 score, longer operating time, no spondylolisthesis; and 3) non-users who became users: more comorbidities, longer symptom duration, higher PHQ9 score, and longer LOS, no spondylolisthesis diagnosis. The majority of spine surgery patients are not taking opioids at one-year postoperatively. This includes two-thirds of those that were taking opioids prior to surgery. Further study of the 1-in-5 patients who are persistent or new users at follow-up is required in order to identify possible modifiable baseline risk factors and develop targeted mitigation strategies in the perioperative period.