Oakland, CA – The decline in opioid use in California workers’ compensation has outpaced the decline among the state’s overall population according to a new California Workers’ Compensation Institute (CWCI) analysis of 2017-2023 opioid prescription data from the California Department of Justice’s Controlled Substance Utilization Review and Evaluation System (CURES) database.

The analysis builds on prior CWCI studies by tracking multiple opioid utilization metrics, noting the percentage change in the number of opioid patients over the study period, changes in the average strength of the daily dose of morphine equivalents (the “morphine equivalent dose” or MED), and the average duration of opioid use for workers’ comp opioid patients. Duration of use and MED level are highly correlated with addiction and harmful side effects of opioids, including overdose and overdose-related death. The study also compares these metrics to opioid treatment guidelines to identify the proportion of patients whose opioid use exceeded guideline recommendations and how these proportions changed over time. Key findings include:

• Nearly 22.3 million Californians were prescribed opioids between 2017 and 2023, with workers’ comp patients accounting for 1.1% of that total. The number of Californians who were prescribed opioids each year fell 34% from 6.8 million in 2017 (17.3% of the population) to 4.5 million in 2023 (11.5% of the population), while the number of workers’ comp patients prescribed opioids fell 62% from 91,620 in 2017 to 34,744 in 2023.
• Breaking the opioid utilization results out by level of patient acuity showed that:
  • The number of acute opioid workers’ comp patients (<30 days of opioid use) declined an average of 9.2% per year vs. 4.9% for all acute California opioid patients.
  • The number of subacute opioid workers’ comp patients (30-89 days of opioid use) declined an average of 12.6% per year vs. 9.8% for all subacute California opioid patients.
  • The number of chronic opioid workers’ comp patients (90 or more days) declined an average of 10.6% per year vs. 6.3% for all chronic California opioid patients.
•  Over the study period the average daily morphine equivalent dose for workers’ comp patients declined across the board, falling 26% for chronic patients, 23.6% for acute patients, and 17.6% for subacute patients. The proportion of new acute workers’ comp patients that exceeded the recommended 50 MED per day threshold fell by 9.9 percentage points and the proportion that was within the 20-50 MED range rose by 13.3 percentage points.
• The proportion of new acute workers’ comp patients receiving opioid prescriptions that exceeded the recommended 5-day supply decreased by 8.2 percentage points during the study period, with 2/3 of that decrease occurring in 2018, immediately after the state incorporated Pain Management and Opioid Treatment Guidelines into the Medical Treatment Utilization Schedule (MTUS) and implemented the MTUS Formulary.
• Among chronic workers’ comp patients, the share of total days’ supply with an MED over 50 dropped from 27.1% in 2017 to 21.3% in 2023.
• During each calendar year in the study period, most workers’ comp chronic opioid patients also received opioid prescriptions from other payer systems, but the percentage of those patients who received opioids from both workers’ compensation and other systems declined from 72.1% in 2017 to 68.7% in 2023.
• From 2017-2023, the total daily morphine equivalent dose (from all payers) for workers’ compensation patients declined by 17.1 MED. The portion of the MED covered by workers’ comp declined by 8.4 MED or 24.1%, the portion covered by other payers declined by 8.6 MED or 32.6%.
• A declining share of workers’ compensation opioid patients had prescriptions in which their days’ supply of opioids from other payers overlapped with their workers’ comp prescriptions. The proportion of days’ supply that overlapped multiple systems declined from 8.0% in 2017 to 3.7% in 2023, so it appears that the declines in opioid utilization in workers’ comp did not lead to increased opioid use in other systems.

While opioid use nationwide has declined across different health care systems, the steep decline in California workers’ compensation, which the CWCI study shows exceeded the decline noted for the general population, reflects the success of reforms enacted over the past two decades. These included a mandate that medical care provided to injured workers conform to evidence-based treatment standards; the addition of Chronic Pain and Opioid Guidelines into the MTUS; implementation of the MTUS Formulary; a requirement that opioid dispensers enter prescription and patient information into CURES within one day of dispensing the drug; and a requirement that doctors check CURES before prescribing a controlled substance to a patient for the first time, and at least once every four months when continuing to prescribe the drugs to the patient.

CWCI has published its study in a Report to the Industry, “Opioid Prescribing for Injured Workers Covered by California Workers’ Compensation System and Other Payers: 2017 – 2023,” which is available at www.cwci.org.