US state policies on opioid prescribing during the peak of the prescription opioid crisis: Associations with opioid overdose mortality

Background: In response to the opioid overdose crisis in the United States, many states implemented policies to guide opioid prescribing, but their impact on overdose mortality (prescription and non-prescription) remains poorly understood. We examined the impact of U.S. state opioid-prescribing policies on opioid overdose mortality following implementation.Methods: We calculated opioid overdose mortality rates from 1999-2016 by U.S. state using the CDC WONDER database, overall and separately for overdose deaths from prescription and non-prescription opioids. For each state, policies active on 1/1/2014 were reviewed for the presence and strength of six provisions recommending judicious opioid prescribing practices; "strong " provisions used the words "should, " "shall, " or "must ". Interrupted time series (ITS) tested the association of each strong provision with overdose mortality, overall and separately for prescription and non-prescription opioids, in the two years following implementation. Sensitivity analyses compared between states, used time-lagged analyses, and excluded synthetic opioids from non-prescription opioid deaths.Results: All six provisions had consistent direction of effect in ITS and sensitivity analyses. Strong provisions for prescriber training and limits on opioid dose reduced the slope of overall and prescription opioid overdose mortality in both ITS and sensitivity analyses. Reduced non-prescription opioid overdose mortality was only associated with strong provision for prescriber training. Some provisions had a negative impact. In ITS, strong provision for prescriber response to misuse increased the slope of non-prescription opioid overdose mortality. Strong provision for mandatory prescription drug monitoring program use had no relationship with overdose mortality in ITS and was associated with increased overall, prescription and non-prescription opioid overdose mortality in between-state sensitivity analysis.Conclusion: Opioid prescribing policies in U.S. states at the peak of the prescription opioid epidemic had modest mortality benefit, and did not reduce non-prescription opioid overdose mortality. A strong provision for prescriber training was the only provision associated with reduced prescription and non-prescription opioid overdose mor-tality. These findings can inform future efforts addressing prescription drug epidemics.