Effects of County-Level Opioid Dispensing Rates on Individual-Level Patterns of Prescription Opioid and Heroin Consumption: Evidence From National U.S. Data.

The authors examined directly whether county-level changes in opioid dispensing rates affect individual-level prescription opioid misuse, frequency of use, and dependence, as well as the same outcomes for heroin. Using data from the restricted-access National Survey on Drug Use and Health, the Centers for Disease Control and Prevention's retail opioid prescription database, the Prescription Drug Abuse Policy System, and the U.S. Census, the authors applied fixed-effects models to determine whether county-level dispensing rates affected prescription opioid outcomes as intended and whether changes in rates adversely affected heroin use outcomes. Bayes factors were used to confirm evidence for null findings. The sample included 748,800 respondents age 12 and older from 2006 to 2016. The odds of prescription opioid misuse, increased frequency of misuse, and dependence were 7.2%, 3.5%, and 10.4% higher, respectively, per standard deviation increase in the county-level opioid dispensing rate per 100 persons. There was no evidence for any association between opioid dispensing rates and the three heroin outcomes. The odds ratio was nonsignificant according to frequentist techniques in fixed-effects models, and Bayesian techniques confirmed very strong support for the null hypothesis. County-level opioid dispensing rates are directly associated with individual-level prescription opioid misuse, frequency of misuse, and dependence. Changes in dispensing were not associated with population shifts in heroin use. Reductions in opioid dispensing rates have contributed to stemming prior increases in prescription opioid misuse while not adversely affecting heroin use. Physicians and other health care providers can take action to minimize opioid dispensing for tangible benefits regarding prescription opioid misuse without adverse effects on heroin use.