The California Workers’ Compensation Institute (CWCI) has published a new study showing that increasing numbers of opioid prescriptions for back conditions among California injured workers were associated with higher overall medical costs, increased lost time from work and more attorney involvement. The study adds to a growing body of knowledge questioning the use of high levels of opioids in the treatment of chronic non-malignant pain.

The study analyzed more than 166,000 California work injury claims for back conditions with no spinal cord involvement (the most common job injury in the state) and found that one in four workers with these conditions received opioids, with those workers averaging more than five opioid prescriptions over the course of treatment. After controlling for claimant occupation, wages, demographic factors, the nature and cause of injury, drug interactions, and other variables, CWCI found that injured workers who received modest levels of opioids — one prescription or less than 240 morphine equivalent milligrams — had claim costs and other outcomes similar to those who received no opioids. Beyond that, however, greater numbers of opioid prescriptions and morphine equivalent milligrams were associated with higher costs and a higher prevalence of adverse outcomes such as increased likelihood of lost time from work and a longer duration of paid temporary disability. Among those with more than seven opioid prescriptions, average claim cost increased three fold and the number of days away from work increased an average of 4.7 times.

The study adds to scientific literature that suggests that opioids have an adverse impact on both activity levels and on self-efficacy, and that prolonged administration of pain medication may impede rather than facilitate injured workers’ recovery from occupational back injuries. CWCI has released the findings in a Report to the Industry, Pain Management and the Use of Opioids in the Treatment of Back Conditions in the California Workers’ Compensation System, which may be ordered from the online store at www.cwci.org. The timing of the report coincides with the release of proposed regulations regarding chronic pain treatment guidelines, which include a section on the use of opioids to treat chronic pain. The state will hold hearings on the proposed regulations August 11 in Los Angeles and August 12 in San Francisco.