A prior authorization policy for extended-release/long-acting opioids may help reduce the number of opioid-naive patients who initiate extended-release/long-acting opioid use but may also increase the rate of short-acting opioid prescriptions, according to a study published in Addiction.
Investigators conducted a retrospective study to examine the effects of a prior authorization policy on prescription drug use, opioid-related emergency department visits, and hospitalizations. They used a difference-in-differences approach to compare the fee-for-service Medicaid programs implemented in Oklahoma (intervention) and Oregon (control).
Participants were Medicaid beneficiaries (mean age, 38 years) who had been prescribed ≥1 fill of an opioid medication between July 2007 and June 2009. Pharmacy claims data were used to estimate several outcomes of opioid use and potential indicators of high-risk use, misuse, and abuse.
Number of new extended-release/long-acting opioid prescription fills in opioid-naive patients (no opioids taken in the prior 30 days) was the study’s primary outcome. The prior authorization policy in Oklahoma was associated with a 0.7 percentage point reduction (95% CI, -1.16 to -0.33 percentage points) in likelihood of incident opioid-naive extended-release/long-acting opioid use, a 1.4 percentage point reduction (95% CI, -2.1 to -0.7 percentage points) in any new extended-release/long-acting opioid prescription claims, and a 1.6 percentage point reduction (95% CI, -0.29 to -0.041) in the number of extended-release/long-acting opioid prescriptions filled per enrollee.
Implementation of the policy also led to an increase (0.36 percentage point) in the number of short-acting opioids fills and in the number of opioids/benzodiazepine coprescriptions (1.1 percentage point). The rate of emergency department visits and hospitalizations did not differ between groups.
Researchers noted several limitations to their study, including potential coding errors and an inability to test parallel pretrend assumptions.
“The policy implementation appears to have reduced [extended-release/long-acting] opioid use, however the small increase in opioid persistence merits further study in larger samples. Given the inherent risks associated with [extended-release/long-acting] opioid formulations, a small increase in short-acting opioid use may be preferable,” concluded the study authors.
Keast S, Kim H, Deyo RA, et al. Effects of a prior authorization policy for extended-release/long-acting opioids on utilization and outcomes in a state Medicaid program [published online April 20, 2018]. Addiction. doi: 10.1111/add.14248