A dynamic model of the opioid drug epidemic with implications for policy

Am J Drug Alcohol Abuse. 2021 Jan 2;47(1):5-15. doi: 10.1080/00952990.2020.1755677. Epub 2020 Jun 9.

Abstract

Background: The U.S. opioid epidemic has caused substantial harm for over 20 years. Policy interventions have had limited impact and sometimes backfired. Experts recommend a systems modeling approach to address the complexities of opioid policymaking.Objectives: Develop a system dynamics simulation model that reflects the complexities and can anticipate intended and unintended intervention effects.Methods: The model was developed from literature review and data gathering. Its outputs, starting in 1990, were compared against 12 historical time series. Four illustrative interventions were simulated for 2020-2030: reducing prescription dosage by 20%, cutting diversion by 30%, increasing addiction treatment from 45% to 65%, and increasing lay naloxone use from 4% to 20%. Sensitivity testing was performed to determine effects of uncertainties. No human subjects were studied.Results: The model fits historical data well with error percentage averaging 9% across 201 data points. Interventions to reduce dosage and diversion reduce the number of persons with opioid use disorder (PWOUD) by 11% and 16%, respectively, but each of these interventions reduces overdoses by only 1%. Boosting treatment reduces overdoses by 3% but increases PWOUD by 1%. Expanding naloxone reduces overdose deaths by 12% but increases PWOUD by 2% and overdoses by 3%. Combining all four interventions reduces PWOUD by 24%, overdoses by 4%, and deaths by 18%. Uncertainties may affect these numerical results, but policy findings are unchanged.Conclusion: No single intervention significantly reduces both PWOUD and overdose deaths, but a combination strategy can do so. Entering the 2020s, only protective measures like naloxone expansion could significantly reduce overdose deaths.

Keywords: Opioid epidemic; fentanyl; historical time series; illicit market; naloxone; policy intervention; simulation model; system dynamics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics, Opioid / therapeutic use
  • Computer Simulation / statistics & numerical data*
  • Drug Overdose / drug therapy
  • Health Policy*
  • Humans
  • Naloxone / therapeutic use
  • Narcotic Antagonists / therapeutic use
  • Opioid Epidemic / statistics & numerical data*
  • Opioid-Related Disorders / drug therapy
  • United States

Substances

  • Analgesics, Opioid
  • Narcotic Antagonists
  • Naloxone