A Dynamic Model of the Opioid Drug Epidemic with Implications for Policy

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 1990, were compared against 12 historical time series. 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 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

JAMA Netw Open

IMPORTANCEDeaths due to opioid overdose have tripled in the last decade. Efforts to curb this trend have focused on restricting the prescription opioid supply; however, the near-term effects of such efforts are unknown.OBJECTIVETo project effects of interventions to lower prescription opioid misuse on opioid overdose deaths from 2016 to 2025.DESIGN, SETTING, AND PARTICIPANTSThis system dynamics (mathematical) model of the US opioid epidemic projected outcomes of simulated individuals who engage in nonmedical prescription or illicit opioid use from 2016 to 2025. The analysis was performed in 2018 by retrospectively calibrating the model from 2002 to 2015 data from the National Survey on Drug Use and Health and the Centers for Disease Control and Prevention.INTERVENTIONSComparison of interventions that would lower the incidence of prescription opioid misuse from 2016 to 2025 based on historical trends (a 7.5% reduction per year) and 50% faster than historical trends (an 11.3% reduction per year), vs a circumstance in which the incidence of misuse remained constant after 2015.MAIN OUTCOMES AND MEASURESOpioid overdose deaths from prescription and illicit opioids from 2016 to 2025 under each intervention.RESULTSUnder the status quo, the annual number of opioid overdose deaths is projected to increase from 33 100 in 2015 to 81 700 (95% uncertainty interval [UI], 63 600-101 700) in 2025 (a 147% increase from 2015). From 2016 to 2025, 700 400 (95% UI, 590 200-817 100) individuals in the United States are projected to die from opioid overdose, with 80% of the deaths attributable to illicit opioids. The number of individuals using illicit opioids is projected to increase by 61%\u2014from 0.93 million (95% UI, 0.83-1.03 million) in 2015 to 1.50 million (95% UI, 0.98-2.22 million) by 2025. Across all interventions tested, further lowering the incidence of prescription opioid misuse from 2015 levels is projected to decrease overdose deaths by only 3.0% to 5.3%.CONCLUSIONS AND RELEVANCEThis study\u2019s findings suggest that interventions targeting prescription opioid misuse such as prescription monitoring programs may have a modest effect, at best, on the number of opioid overdose deaths in the near future. Additional policy interventions are urgently needed to change the course of the epidemic.20192019-03-13T00:00:00ZK23 DA042168/DA/NIDA NIH HHS/United StatesU01 CE002780/CE/NCIPC CDC HHS/United States30707224PMC64159661060

Injury, Infection, and Recovery from Opioid Use Disorders in Michigan

The opioid crisis is an ongoing serious public health challenge in the United States. Starting in the late 1990s, increases in prescriptions for opioid pharmaceuticals led to increases in nonmedical prescription opioid use and, in some cases, subsequent heroin use. These changes have had significant impacts on public health. Drug overdose mortality quadrupled between 1999 and 2016 and increases in injection drug use have led to a rise in bloodborne viral infections. Improving substance use disorder treatment outcomes is a major public health priority; 40-60% treated for a substance use disorder relapse within a year of completing treatment. This dissertation explored three public health priorities related to the opioid crisis: injury, infection, and recovery. In chapter 2, we focused on injury prevention by examining overdose experiences, naloxone knowledge, attitudes towards overdose risk, and justice involvement among a sample of adults who used opioids in a justice diversion addiction treatment program in Michigan. We used latent class analysis to identify two general justice involvement patterns that occurred prior to treatment: the first was characterized by many recent arrests and little incarceration time, and the second involved incarceration prior to diversion. Only 56.2% of participants had heard of naloxone and identified it as an overdose treatment, yet 68.1% had experienced and 79.2% had witnessed an overdose. These results highlighted the universal need for overdose education and naloxone distribution in the justice diversion addiction treatment setting. In chapter 3, we characterized the potential impact of interventions to combat the growing incidence of hepatitis C virus (HCV) infection among young people who inject drugs (PWID). We developed an age-stratified ordinary differential equation HCV transmission model fit to surveillance data from Michigan. We predicted that treating 10% of PWID per year in Michigan could reduce HCV cases by over half. Coupling HCV treatment with behavioral interventions could further reduce HCV incidence and prevalence. In chapter 4, we explored a potential new target for adjunctive treatments to promote recovery from opioid use disorders by examining how substance use impacts the gut microbiota. The gut microbiota is the community of living bacteria in the human gut. It is increasingly recognized as an important communicator along the gut-brain axis, the crosstalk pathways between the gut and brain, and may also modify psychopathology. We studied 46 patients receiving outpatient addiction treatment in Michigan who were exposed to opioid agonists (prescription opioids and heroin) and antagonists (naltrexone or naloxone). We found that opioid agonist exposure tended to decrease bacterial community diversity and was associated with lower abundance of Roseburia, a butyrate producer, and Bilophila, a microbe important in bile acid metabolism. We did not find these changes in participants who were concurrently or singly exposed to opioid antagonists. These findings were consistent with those from murine models of morphine exposure and highlighted directions for future work that further explores whether psycho-adjunctive treatments that promote gut health could improve opioid use disorder treatment outcomes. In chapter 5, I close by highlighting some of the lessons I learned through my dissertation work, and propose new research avenues within the areas of injury, infection, and recovery, that focus on mitigating the negative impacts of the opioid crisis on public health.PHDEpidemiological ScienceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145991/1/rgic_1.pd

Pharmacists\u27 Role in Opioid Use Disorder and Overdose Prevention and Treatment and Their Attitudes and Perceptions Towards Distributing Naloxone Under a Standing Order

Background: Opioids are a class of drugs that bind to opioid receptors (mu, delta, and kappa), located in the central and peripheral nervous systems, to exert responses such as analgesia, respiratory depression, euphoria, and miosis. The opioid epidemic is characterized in large part by an increase in opioid overdose deaths. Community pharmacists are one of the most accessible healthcare professionals who frequently interact with patients and can implement OUD and opioid overdose prevention strategies. Treatment for opioid overdose and OUD include naloxone for overdose deaths as well as medication-assisted treatment for OUD. Objective: The specific aims of this thesis include i) to explore community pharmacists’ attitudes, subjective norm, perceived behavioral control, and behavioral intention towards dispensing opioid receptor antagonists (ORAs) under a standing order in Virginia and ii) to evaluate the cost-effectiveness of SSP alone, MOUD alone, and SSP+MOUD combination in preventing HCV cases among opioid IDUs in the US. Methods: A broad search strategy of terms relevant to OUD was used to find evidence of pharmacist involvement in OUD management from PubMed/MEDLINE. Articles were excluded if not related to pharmacist OUD management, including pain management, not related to pharmacy practice, not involving OUD, or not relating to the opioid epidemic. The first aim was assessed by conducting semi-structured interviews of community pharmacists across Virginia between June 2018 – October 2019. The interview guide was based on the Theory of Planned Behavior. Interviews were recorded, transcribed verbatim, and thematically analyzed. The second aim assessed cost-effectiveness from a public payer perspective over a one-year time horizon by using a decision-tree analysis model based on published literature and publicly available data. Results: Pharmacists were confused about the specifics and the processes involved with dispensing naloxone under the standing order. Furthermore, many recognized the underuse of the standing order. Community pharmacists in Virginia expressed mixed intentions toward dispensing ORAs under the standing order. The incremental cost savings per HCV case avoided per 100 opioid IDUs compared to “no intervention” were as follows: SSP+MOUD combination = $347,573; SSP alone =$363,821; MOUD alone = $317,428. The ICER for the combined strategy was$4,699 compared to SSP group. Sensitivity analysis showed that the results of the base case cost-effectiveness analysis were sensitive to variations in the probabilities of injection-risk behavior for the SSP and SSP+MOUD combination groups, probability of NO HCV with “no intervention”, and costs of MOUD and HCV antiviral. Conclusions: Pharmacists expressed mixed behavioral intention toward dispensing ORAs under the standing order. Future research should focus on quantifying the uptake of the standing order at the state level. The SSP+MOUD combination and SSP alone strategies dominate MOUD alone and “no intervention” strategies. Pharmacists may incorporate a combination strategy as it is shown to be cost-effective if payers were willing to pay $4,699 or more per case of HCV avoided. Although these harm reduction programs will provide benefits in a one-year time frame, the largest benefit may become evident in the years ahead

Survey of U.S. Undergraduate Self-Reported Opioid Diversion and Heroin use, Motives, Sources, and Collective Efficacy as Mediating Factors

Epic morbidity and mortality, and intractability make prescription opioid diversion a wicked problem. Meanwhile, college undergraduates are vulnerable to opioid misuse and its consequences. The purpose of this quantitative study was to assess U.S. undergraduate students\u27 opioid misuse and the relationship between mediating factors. The study\u27s theoretical framework rested on Wakeland\u27s et al. opioid system model and Shaw and McKay\u27s social disorganization theory. This study bridged the gap, measuring collective efficacy and testing its relationship to undergraduate decisions to regulate misuse. Thus, research questions focused on gauging the problem\u27s scope and assessing relationships between factors that drive or potentially regulate diversion. The Campus Opioid Diversion Survey, designed for this study, was administered to a nonrandom, undergraduate survey panel (N = 434), revealing past year opioid misuse at 6.9% and heroin use at 2.9%. While a chi-square test revealed no significant relationship between motives and sources for misuse, significant relationships were found between filling a prescription for opioids and misuse, between opioid and heroin use, and between observing the negative consequences of misuse and social action. An independent samples t-test showed a significant relationship between collective efficacy and social action. Findings show campus diversion remains an emerging health and safety issue, but that collective efficacy indicates a capacity for regulation. Anticipating misuse, public safety stakeholders should complement responses to diversion schemes with continuous assessment, communications that empower student-citizens, and focused promotion of social cohesion that will fuel mitigation via social action aimed at social change

Curr Epidemiol Rep

Purpose of review:System dynamics (SD) is an approach to solving problems in the context of dynamic complexity. The purpose of this review was to summarize SD applications in injury prevention and highlight opportunities for SD to contribute to injury prevention research and practice.Recent findings:While SD has been increasingly used to study public health problems over the last few decades, uptake in the injury field has been slow. We identified 18 studies, mostly conducted in the last 10 years. Applications covered a range of topics (e.g., road traffic injury; overdose; violence), employed different types of SD tools (i.e., qualitative and quantitative), and served a variety of research and practice purposes (e.g., deepen understanding of a problem, policy analysis).Summary:Given the many ways that SD can add value and complement traditional research and practice approaches (e.g., through novel stakeholder engagement and policy analysis tools), increased investment in SD-related capacity building and opportunities that support SD use are warranted.R49 CE002479/CE/NCIPC CDC HHS/United States2020-06-15T00:00:00Z31911889PMC69458207811vault:3438

A Mathematical Model of the Opioid Epidemic in the State of Maine

For the past two decades the United States has been embroiled in a prescription drug epidemic that has since grown in magnitude and complexity. The ripples of this epidemic have been especially apparent in the state of Maine, which has fought hard to mitigate the damage caused by addiction to pharmaceutical and illicit opioids. Us- ing data from state and federal sources, we construct a mathematical model capturing the dynamics of the opioid epidemic in the state of Maine, specifically as it pertains to pharmaceutical opioids and heroin. Parameter fitting is performed followed by an uncertainty analysis to quantify potential error in parameter estimates. The model is analyzed to determine effective ways of controlling opioid abuse prevalence (both in the form of heroin and pharmaceutical opioid use) at different points in time, and stochastic simulations are run to test the effect of various control strategies on the number of opioid abusers in the system. These results are then presented with the hope of helping to inform public policy as to the most effective means of intervention

Anhedonia modulates benzodiazepine and opioid demand among persons in treatment for opioid use disorder

BACKGROUND: Benzodiazepine (BZD) misuse is a significant public health problem, particularly in conjunction with opioid use, due to increased risks of overdose and death. One putative mechanism underlying BZD misuse is affective dysregulation, via exaggerated negative affect (e.g., anxiety, depression, stress-reactivity) and/or impaired positive affect (anhedonia). Similar to other misused substances, BZD consumption is sensitive to price and individual differences. Although purchase tasks and demand curve analysis can shed light on determinants of substance use, few studies have examined BZD demand, nor factors related to demand. METHODS: This ongoing study is examining simulated economic demand for alprazolam (among BZD lifetime misusers based on self-report and DSM-5 diagnosis; n = 23 total; 14 male, 9 female) and each participant\u27s preferred-opioid/route using hypothetical purchase tasks among patients with opioid use disorder (n = 59 total; 38 male, 21 female) who are not clinically stable, i.e., defined as being early in treatment or in treatment longer but with recent substance use. Aims are to determine whether: (1) BZD misusers differ from never-misusers on preferred-opioid economic demand, affective dysregulation (using questionnaire and performance measures), insomnia/behavioral alertness, psychiatric diagnoses or medications, or urinalysis results; and (2) alprazolam demand among BZD misusers is related to affective dysregulation or other measures. RESULTS: Lifetime BZD misuse is significantly (p \u3c 0.05) related to current major depressive disorder diagnosis, opioid-negative and methadone-negative urinalysis, higher trait anxiety, greater self-reported affective dysregulation, and younger age, but not preferred-opioid demand or insomnia/behavioral alertness. Alprazolam and opioid demand are each significantly positively related to higher anhedonia and, to a lesser extent, depression symptoms but no other measures of negative-affective dysregulation, psychiatric conditions or medications (including opioid agonist therapy or inpatient/outpatient treatment modality), or sleep-related problems. CONCLUSION: Anhedonia (positive-affective deficit) robustly predicted increased BZD and opioid demand; these factors could modulate treatment response. Routine assessment and effective treatment of anhedonia in populations with concurrent opioid and sedative use disorder may improve treatment outcomes

Health Insurance Coverage, Sociodemographic Factors, and Treatment Completion for Opioid Abusers in Indiana

Many accidental deaths have recently occurred in Indiana due to opioid overdose. The current study sought to assess the association between sociodemographic factors, health insurance, and successful treatment completion for opioids abusers in Indiana based on the existing literature gap. In this study, the dependent variables considered were treatment completion status and opioid abuse. The independent variables included health insurance coverage and sociodemographic factors of education, marital status, employment status, race, gender, and age. I measured both dependent and independent variables as categorical. A cross-sectional and quantitative research approach was used by analyzing data from the 2017-Treatment Episode Data Set Discharges (TEDS-D) using the Statistical Package for the Social Sciences (SPSS) version 25.0.Descriptive statistics, chi-square, bivariate, and multivariate logistic regression were applied to evaluate the association. Significant findings revealed that individuals in “not in labor force” were 2.0 times more likely [OR=2.042, 95% CI (1.853, 2.252), p\u3c0.0001], unemployed were 1.8 times more likely [OR=1.785, 95% CI (1.662, 1.916), p\u3c0.0001], and part-timers were 1.4 times more likely [OR=1.406, 95% (1.269, 1.557), p\u3c0.0001] to complete treatment compared to full-time workers. The outcomes showed that compared to insured, uninsured individuals were less likely [OR=0.704, 95% CI (0.662, 0.749), p\u3c0.0001] to complete treatment. Intervention plans such as increasing screening among vulnerable populations, mass education, and advocacy for health insurance coverage could promote positive social change by decreasing opioid-related mortality and improving treatment outcomes in Indiana