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. 2023 Jul 17;23(1):760.
doi: 10.1186/s12913-023-09773-1.

A multimorbidity model for estimating health outcomes from the syndemic of injection drug use and associated infections in the United States

John J Chiosi  1   2 , Peter P Mueller  3 , Jagpreet Chhatwal  4   3 , Andrea L Ciaranello  5   4
Affiliations

A multimorbidity model for estimating health outcomes from the syndemic of injection drug use and associated infections in the United States

John J Chiosi et al. BMC Health Serv Res. .

Abstract

Background: Fatal drug overdoses and serious injection-related infections are rising in the US. Multiple concurrent infections in people who inject drugs (PWID) exacerbate poor health outcomes, but little is known about how the synergy among infections compounds clinical outcomes and costs. Injection drug use (IDU) converges multiple epidemics into a syndemic in the US, including opioid use and HIV. Estimated rates of new injection-related infections in the US are limited due to widely varying estimates of the number of PWID in the US, and in the absence of clinical trials and nationally representative longitudinal observational studies of PWID, simulation models provide important insights to policymakers for informed decisions.

Methods: We developed and validated a MultimorbiditY model to Reduce Infections Associated with Drug use (MYRIAD). This microsimulation model of drug use and associated infections (HIV, hepatitis C virus [HCV], and severe bacterial infections) uses inputs derived from published data to estimate national level trends in the US. We used Latin hypercube sampling to calibrate model output against published data from 2015 to 2019 for fatal opioid overdose rates. We internally validated the model for HIV and HCV incidence and bacterial infection hospitalization rates among PWID. We identified best fitting parameter sets that met pre-established goodness-of-fit targets using the Pearson's chi-square test. We externally validated the model by comparing model output to published fatal opioid overdose rates from 2020.

Results: Out of 100 sample parameter sets for opioid use, the model produced 3 sets with well-fitting results to key calibration targets for fatal opioid overdose rates with Pearson's chi-square test ranging from 1.56E-5 to 2.65E-5, and 2 sets that met validation targets. The model produced well-fitting results within validation targets for HIV and HCV incidence and serious bacterial infection hospitalization rates. From 2015 to 2019, the model estimated 120,000 injection-related overdose deaths, 17,000 new HIV infections, and 144,000 new HCV infections among PWID.

Conclusions: This multimorbidity microsimulation model, populated with data from national surveillance data and published literature, accurately replicated fatal opioid overdose, incidence of HIV and HCV, and serious bacterial infections hospitalization rates. The MYRIAD model of IDU could be an important tool to assess clinical and economic outcomes related to IDU behavior and infections with serious morbidity and mortality for PWID.

Keywords: Bacterial Infections; Drug overdose; Endocarditis; HIV; Hepatitis C; Injection drug use; Opioid use disorder; People who inject drugs; Serious injection related infections; Syndemic.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Schema for the Multimorbidity Model to Reduce Infections Associated with Drug Use (MYRIAD). Notes: HCV: hepatitis C virus; OUD: opioid use disorder; CNS: central nervous system. All persons in the model start in an active injection drug use state within the “low-risk,” “medium-risk,” and “OUD” states
Fig. 2
Fig. 2
Calibration and validation of MYRIAD results to fatal opioid deaths rates among people who misuse opioids in the US from 2015–2020. Notes: CI: confidence interval
See this image and copyright information in PMC

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References

    1. Hedegaard H, Miniño AM, Spencer MR, Warner M. Drug overdose deaths in the United States, 1999–2020. NCHS Data Brief 2021;(426):1–8. - PubMed
    1. Crepaz N, Hess KL, Purcell DW, Irene Hall H. Estimating national rates of HIV infection among MSM, persons who inject drugs, and heterosexuals in the United States. AIDS. 2019;33(4):701–8. doi: 10.1097/QAD.0000000000002111. - DOI - PMC - PubMed
    1. Lucas GM, Griswold M, Gebo KA, Keruly J, Chaisson RE, Moore RD. Illicit drug use and HIV-1 disease progression: a longitudinal study in the era of highly active antiretroviral therapy. Am J Epidemiol. 2006;163(5):412–20. doi: 10.1093/aje/kwj059. - DOI - PubMed
    1. McCarthy NL, Baggs J, See I, et al. Bacterial infections associated with substance use disorders, large cohort of United States Hospitals, 2012–2017. Clin Infect Dis. 2020;71(7):e37–44. doi: 10.1093/cid/ciaa008. - DOI - PMC - PubMed
    1. Lansky A, Finlayson T, Johnson C, et al. Estimating the number of persons who inject drugs in the united states by meta-analysis to calculate national rates of HIV and hepatitis C virus infections. PLoS ONE. 2014;9(5):e97596. doi: 10.1371/journal.pone.0097596. - DOI - PMC - PubMed

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