The effect of state prescription opioid policies on prescribing and overdose deaths

It is important to understand whether and how opioid prescribing policies affect prescribing rates, opioid overdose rates.  In addition, it is important to consider unintended consequences of these policies, as it has been postulated that policies intended to reduce inappropriate opioid prescribing and prescription opioid overdose deaths have unintentionally driven increased heroin use and heroin overdose deaths.

We examined the relationship between state-level prescription opioid policies prescribing and overdose deaths in the United States from 2006-2013.  We employed National Vital Statistics data and IMS prescribing data and estimated the impact of these policies using a difference-in-difference modelling approach to examine the effect of these policies in 38 states and the District of Columbia, with other states excluded because of data validity or other issues.  While we considered all state level policies, we focused on two specific state-level prescription opioid policies whose independent and combined effects were able to be estimated, namely pain clinic laws and mandated provider review of Prescription Drug Monitoring Program (PDMP) data.

We found that the combined policy implementation of these two laws resulted in significant decreases in amounts of opioids prescribed and in prescription opioid-related overdose death rates (─ 0.756 [─ 1.467, ─0.046] per 100,000).  Implementation of pain clinic laws and of pain clinic laws combined with mandated provider review of PDMP data were not related to heroin overdose death rates (─0.706 [─1.587, 0.175] and ─0.035 [─ 0.695, 0.625] per 100,000 respectively). Heroin death rates increased throughout the study period in states that did and in states that did not implement prescription opioid policies, from 0.73 to 2.70 deaths per 100,000 population overall.

Opioid prescribing policies were not associated with significant changes in heroin overdose death rates. Mandated PDMP review combined with pain clinic laws appeared to reduce amounts of opioids prescribed and to reduce opioid-related overdose deaths. States implementing combined policies had experienced greater increases than other states in both heroin and prescription opioid overdose deaths prior to policy implementation, suggesting that observed increases in heroin overdose deaths resulted from factors other than these polices. These factors might include increased heroin supply as well as increased exposure to prescription opioids throughout the United States.