Perioperative opioid demand and risk factors for long-term opioid use among anterior cruciate ligament reconstruction and repair patients in Alberta

• Author / Creator

  Roberts, Richard

• Chapter 2 (Study 1):
  Background: Opioid use beyond typical postoperative pain timelines remains an adverse surgical outcome. Anterior cruciate ligament reconstruction and repair (ACLRR) are common surgeries whose perioperative opioid demands have not been characterized in a Canadian setting.
  Methods: In this retrospective cohort study, we identified ACLRRs performed between 2009–2017 in Alberta among patients aged 10–65. Using linked community pharmacy dispensation data, we evaluated time trends in the percentage of patients with preoperative opioid exposure and in initial postoperative opioid dispensation characteristics for opioid-naïve patients. We described typical month-to-month opioid demand for one year following ACLRR, wherein we distinguished patients exhibiting >90 days of opioid supply (LTOT).
  Results: Across 15,675 ACLRRs, preoperative opioid exposure increased from 2009 (6.6%) to 2016-17 (9.9%). Opioid-naïve patients more frequently received postoperative opioids in 2016–17 (89.2%) than in 2009 (66.7%). By 2016–17, initiating dispensations among opioid-naïve patients became more likely to contain tramadol (49.6%), involve ≥50 morphine milligram equivalent daily dosages (43.6%), and be indicated for use over 5–7 days (57.8%). 304 patients (1.9%) exhibited LTOT during their first postoperative year. LTOT rate was stratified by patient preoperative opioid exposure, ACLRR surgical type, and patient age, but did not significantly change over the study period.
  Conclusion: Perioperative opioid dispensations in ACLRR increased in frequency and dosage from 2009–2017 in Alberta, especially among patients without preoperative opioid exposure, alongside no significant change to overall postoperative LTOT rate. ACLRR-specific clinical guidance may be necessary for future widespread adoption of opioid-sparing and multimodal postoperative analgesia.
  Chapter 3 (Study 2):
  Background: Postoperative long-term opioid therapy (LTOT) provides minimal patient benefit while conferring substantial potential for harm. Among anterior cruciate ligament (ACL) reconstruction and repair (ACLRR) patients, the roles of preoperative non-opioid drug exposure and initial postoperative opioid dispensation characteristics on LTOT have not been elucidated.
  Hypothesis/Purpose: To identify preoperative, intraoperative and postoperative patient-level characteristics associated with changes in LTOT likelihood among patients undergoing ACLRR, while following recommendations to robustly define LTOT and to broadly include initiating opioid dispensation characteristics.
  Study Design: Cohort study.
  Methods: Physician billing codes were used to index ACLRRs performed between 2009–2017 in Alberta, Canada. Patient demographics, comorbidity history, preoperative opioid exposure and preoperative non-opioid drug exposure were determined for all ACLRR following linkage. Initial postoperative opioid dispensations were identified and categorized by dosage and duration for all preoperatively opioid-naïve patients. Associations between patient-level characteristics and postoperative LTOT were described via multivariable logistic regression models using three LTOT outcome constructs of varying stringency. Models were generated for the whole ACLRR cohort, as well as for the subset of patients undergoing ACLRR who were both opioid-naïve and who received opioids within their first 30 postoperative days.
  
  Results: 15,675 ACLRRs were included for analysis. Complete-cohort LTOT prevalence ranged from 304 (1.9%; Primary LTOT) patients to 1,701 (10.9%; Prior studies’ LTOT) patients. Preoperative opioid dispensation showed the strongest association with all LTOT outcome constructs. Other patient-level risk factors associated with increased LTOT included patient age >29, preoperative exposure to antidepressants, antipsychotics, and benzodiazepines; histories of substance use disorder and uncomplicated diabetes; and ACL repair <14 days from injury versus ACL reconstruction. Among patients without preoperative opioid exposure, initiating opioid dispensations of ≥50 morphine milligram equivalent daily dosage and of 15+ day duration were associated with increased LTOT. Patterns of association differed based on LTOT outcome choice.
  Conclusion: Numerous patient-level associations with increased LTOT are present among patients undergoing ACLRR, although preoperative opioid exposure remains a chiefly important predictor. Substantial differences in patterns of association between LTOT outcome constructs indicate a need for use of robust LTOT outcome measures in future research.

• Subjects / Keywords

  • epidemiology
  • public health
  • opioid
  • surgery
  • anterior cruciate ligament
  • perioperative
  • health outcome modeling

• Graduation date

  Fall 2023

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-yam5-2370

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.