Nurse Practitioner Prescriptive Authority and Prescription Opioid Use

This paper uses state differences in the nurse practitioner (NP) market to evaluate the effects of state laws allowing NPs to prescribe controlled substances on prescription opioid use. I study these effects by merging nationwide data from the Medical Expenditure Panel Survey (MEPS) over 18 years (1996-2013) with data on state laws. I then exploit variation in these laws over time to create a quasi-natural experiment and to estimate the causal impact of NP deregulation on prescription opioid use. I find, relative to patients living in more restrictive states, that patients who live in states with more flexible NP laws reduce their prescription opioid use by 7 percent to 9 percent. I also find that health outcomes either slightly improve or remain unaffected by the enactment of these laws. Taken together, these results indicate that NP deregulation slows the trend in prescription opioid growth while potentially improving patient outcomes. Furthermore, suggestive evidence implies that these effects may be even larger for the least restrictive states, opening the door for future reforms.