Rates and risk factors for persistent opioid use after cardiothoracic surgery: A cohort study.

Background: This study's aim was to estimate potential risk factors for persistent opioid use after cardiothoracic surgery.

Methods: This study included participants in the McGill University Health Centre clinical trial (2014 to 2016). Provincial medical services, prescription claims, and medical charts data were linked. Persistent opioid use was defined as an initial peri-operative opioid dispensation followed by an opioid dispensation between 91 and 180 days postdischarge. Multivariable Cox Proportional Hazards models were used to assess factors associated with persistent opioid use.

Results: A cohort of 815 patients (mean age: 68.9 [standard deviation = 8.9]) was assembled, of which 8.2% became persistent opioid users. Factors such as higher Charlson Comorbidity Index (adjusted hazard ratio: 3.4, 95% confidence interval: 1.1-10.6), history of diabetes (adjusted hazard ratio: 2.1, 95% confidence interval: 1.3-3.4), substance and alcohol abuse (adjusted hazard ratio: 16.3, 95% confidence interval: 5.3-49.5), and radiotherapy (adjusted hazard ratio: 2.4, 95% confidence interval: 1.5-4.1) were associated with a higher hazard of persistent opioid use. Previous opioid use (adjusted hazard ratio: 1.7, 95% CI: 1.0-2.8), daily peri-operative opioid dose (adjusted hazard ratio: 2.3, 95% confidence interval: 1.5-3.7), having an opioid dispensation 30 days pre-admission (adjusted hazard ratio: 1.7, 95% confidence interval: 1.0-2.8), and pre-admission analgesic use (adjusted hazard ratio: 1.7, 95% confidence interval: 1.0-2.8), were also associated with an increased hazard of persistent use. Being prescribed multimodal analgesia at discharge (adjusted hazard ratio: 0.54, 95% confidence interval: 0.32-0.92) was associated with a 46% decreased hazard of developing persistent opioid use.

Conclusion: Multiple patient- and medication-related characteristics were associated with an increased hazard of persistent opioid use.