(217) Patterns of opioid doses to compensated Australian workers with low back pain

Background: Low back pain (LBP) is the most prevalent musculoskeletal condition and is the leading cause of disability worldwide. Although clinical guidelines advocate for non-pharmacologic approaches as the initial treatment for LBP, one in three injured workers with LBP were dispensed opioids at least once during their claim. The use of opioids for the treatment of non-malignant chronic pain has been reported as a significant driver of medical and indemnity expenses in workers’ compensation.

Objectives: This study aims to identify patterns of opioid prescription to compensated workers in Victoria and examine the characteristics of injured workers who are at risk of high volume and long-term opioid use.

Methods: We included workers with accepted workers’ compensation claims for low back pain with at least one day of scheme-funded income replacement, received by an insurer between 01 January 2010 and 30 June 2016 across Victoria. Trajectory modelling was used to identify different opioid dispensing patterns. Descriptive statistics and logistic regression were used to report the proportion of worker sociodemographic characteristics and compare sociodemographic characteristics between each opioid dispensing pattern group.

Results: Among all claims, 33.1% reported receiving any opioid medications as part of their claims. Six opioid dispensing patterns were identified. Individuals in the highest socioeconomic status (SES) quintile were less likely to receive long-term, high-dose opioids (OR 0.57, 99%CI 0.33 to 0.97) compared to other quintiles. Workers who were ever dispensed gabapentinoids and antidepressants were 7.93 (99%CI 5.39 to 11.67) times and 22.29 (99%CI 14.61 to 34.00) times as likely to use long-term high-dose opioids respectively relative to workers with a single opioid dispensing. Those who had surgery were 1.69 (99%CI 1.20 to 2.37) times as likely to use long-term high-dose opioids compared to non-surgery group.

Conclusions: Lower socioeconomic status, having ever taken gabapentinoids or antidepressants or having had surgery are all associated with the development of long-term opioid use among compensated workers. Regulation on opioid prescriptions, strengthening clinician oversight of patients' medication histories, and promoting non-opioid treatments within the workers' compensation system may represent crucial directions for future implications.