Faculty Bibliography

BACKGROUND AND AIMS/OBJECTIVE:Persons with substance use disorders (SUDs) are at elevated risk of suicide death. We identified novel risk factors and interactions that predict suicide among men and women with SUD using machine learning. DESIGN/METHODS:Case-cohort study. SETTING/METHODS:Denmark. PARTICIPANTS/METHODS:The sample was restricted to persons with their first SUD diagnosis during 1995 to 2015. Cases were persons who died by suicide in Denmark during 1995 to 2015 (n = 2774) and the comparison subcohort was a 5% random sample of individuals in Denmark on 1 January 1995 (n = 13 179). MEASUREMENTS/METHODS:Suicide death was recorded in the Danish Cause of Death Registry. Predictors included social and demographic information, mental and physical health diagnoses, surgeries, medications, and poisonings. FINDINGS/RESULTS:Persons among the highest risk for suicide, as identified by the classification trees, were men prescribed antidepressants in the 4 years before suicide and had a poisoning diagnosis in the 4 years before suicide; and women who were 30+ years old and had a poisoning diagnosis 4 years before and 12 months before suicide. Among men with SUD, the random forest identified five variables that were most important in predicting suicide; reaction to severe stress and adjustment disorders, drugs used to treat addictive disorders, age 30+ years, antidepressant use, and poisoning in the 4 prior years. Among women with SUD, the random forest found that the most important predictors of suicide were prior poisonings and reaction to severe stress and adjustment disorders. Individuals in the top 5% of predicted risk accounted for 15% of all suicide deaths among men and 24% of all suicides among women. CONCLUSIONS:In Denmark, prior poisoning and comorbid psychiatric disorders may be among the most important indicators of suicide risk among persons with substance use disorders, particularly among women.

OBJECTIVES:The rapid increase in opioid overdose and opioid use disorder (OUD) over the past 20 years is a complex problem associated with significant economic costs for healthcare systems and society. Simulation models have been developed to capture and identify ways to manage this complexity and to evaluate the potential costs of different strategies to reduce overdoses and OUD. A review of simulation-based economic evaluations is warranted to fully characterize this set of literature. METHODS:A systematic review of simulation-based economic evaluation (SBEE) studies in opioid research was initiated by searches in PubMed, EMBASE, and EbscoHOST. Extraction of a predefined set of items and a quality assessment were performed for each study. RESULTS:The screening process resulted in 23 SBEE studies ranging by year of publication from 1999 to 2019. Methodological quality of the cost analyses was moderately high. The most frequently evaluated strategies were methadone and buprenorphine maintenance treatments; the only harm reduction strategy explored was naloxone distribution. These strategies were consistently found to be cost-effective, especially naloxone distribution and methadone maintenance. Prevention strategies were limited to abuse-deterrent opioid formulations. Less than half (39%) of analyses adopted a societal perspective in their estimation of costs and effects from an opioid-related intervention. Prevention strategies and studies' accounting for patient and physician preference, changing costs, or result stratification were largely ignored in these SBEEs. CONCLUSION:The review shows consistently favorable cost analysis findings for naloxone distribution strategies and opioid agonist treatments and identifies major gaps for future research.

BACKGROUND:The COVID-19 pandemic is creating severe issues for healthcare and broad social structures, exposing societal vulnerabilities. Among the populations affected by COVID-19 are people engaged in substance use, such as people who smoke; vape (e-cigarette use); use opioids, cannabis, alcohol, or psychoactive prescription drugs; or have a substance use disorder (SUD). Monitoring substance use and SUD during the pandemic is essential, as people who engage in substance use or present with SUD are at greater risk for COVID-19, and the economic and social changes resulting from the pandemic may aggravate SUD. There have been several reviews focused on COVID-19 in relation to substance use and SUD. Reviews generally did not consider on a large range of substance use variants or SUDs. We plan a scoping review that seeks to fill gaps in our current understanding of substance use and SUD, in the COVID-19 era. METHODS:A scoping review focused on substance use and SUD, in relation to COVID-19, will be conducted. We will search (from January 2020 onwards) Cumulative Index to Nursing and Allied Health Literature, Africa-Wide Information, Web of Science Core Collection, Embase, Global Health, WHO Global Literature on Coronavirus Disease Database, WHO Global Index Medicus, PsycINFO, PubMed, Middle Eastern Central Asian Studies, CINAHL Complete, and Sociological Abstracts. Grey literature will be identified using Disaster Lit, Google Scholar, HSRProj, governmental websites, and clinical trials registries (e.g., ClinicalTrial.gov , World Health Organization, International Clinical Trials Registry Platform and International Standard Randomized Con-trolled Trial Number registry). Study selection will conform to Joanna Briggs Institute Reviewers' Manual 2015 Methodology for JBI Scoping Reviews. Only English language, original studies investigating substance use and SUD, in relation to COVID-19 in all populations and settings, will be considered for inclusion. Two reviewers will independently screen all citations, full-text articles, and abstract data. A narrative summary of findings will be conducted. Data analysis will involve quantitative (e.g., frequencies) and qualitative (e.g., content and thematic analysis) methods. DISCUSSION:Original research is urgently needed to mitigate the risks of COVID-19 on substance use and SUD. The planned scoping review will help to address this gap. SYSTEMATIC REVIEW REGISTRATION:Open Science Framework (osf/io/tzgm5).

Coronavirus disease 2019 (COVID-19) will have a lasting impact on public health. In addition to the direct effects of COVID-19 infection, physical distancing and quarantine interventions have indirect effects on health. While necessary, physical distancing interventions to control the spread of COVID-19 could have multiple impacts on people living with opioid use disorder, including impacts on mental health that lead to greater substance use, the availability of drug supply, the ways that people use drugs, treatment-seeking behaviors, and retention in care. The degree to which COVID-19 will impact the opioid epidemic and through which of the possible mechanisms that we discuss is important to monitor. We employed simulation modeling to demonstrate the potential impact of physical distancing on overdose mortality.

More than 750,000 people in the United States died from an overdose between 1999 and 2018; two-thirds of those deaths involved an opioid. In this review, we present trends in opioid overdose rates during this period and discuss how the proliferation of opioid prescribing to treat chronic pain, changes in the heroin and illegally manufactured opioid synthetics markets, and social factors, including deindustrialization and concentrated poverty, contributed to the rise of the overdose epidemic. We also examine how current policies implemented to address the overdose epidemic may have contributed to reducing prescription opioid overdoses but increased overdoses involving illegal opioids. Finally, we identify new directions for research to understand the causes and solutions to this critical public health problem, including research on heterogeneous policy effects across social groups, effective approaches to reduce overdoses of illegal opioids, and the role of social contexts in shaping policy implementation and impact. Expected final online publication date for the Annual Review of Public Health, Volume 42 is April 1, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

BACKGROUND:The rapid growth of opioid abuse and related mortality across the United States has spurred the development of predictive models for the allocation of public health resources. These models should characterize heterogeneous growth across states using a drug epidemic framework that enables assessments of epidemic onset, rates of growth, and limited capacities for epidemic growth. METHODS:We used opioid overdose mortality data for 146 North and South Carolina counties from 2001 through 2014 to compare the retrodictive and predictive performance of a logistic growth model that parameterizes onsets, growth, and carrying capacity within a traditional Bayesian Poisson space-time model. RESULTS:In fitting the models to past data, the performance of the logistic growth model was superior to the standard Bayesian Poisson space-time model (deviance information criterion: 8088 vs. 8256), with reduced spatial and independent errors. Predictively, the logistic model more accurately estimated fatality rates 1, 2, and 3 years in the future (root mean squared error medians were lower for 95.7% of counties from 2012 to 2014). Capacity limits were higher in counties with greater population size, percent population age 45 to 64, and percent white population. Epidemic onset was associated with greater same-year and past-year incidence of overdose hospitalizations. CONCLUSION/CONCLUSIONS:Growth in annual rates of opioid fatalities was capacity limited, heterogeneous across counties, and spatially correlated, requiring spatial epidemic models for the accurate and reliable prediction of future outcomes related to opioid abuse. Indicators of risk are identifiable and can be used to predict future mortality outcomes.

PURPOSE/OBJECTIVE:Individuals with poor physical and mental health may face elevated risk for suicide, particularly suicide by firearm. METHODS:This retrospective cohort study used statewide, longitudinally-linked ED patient record and mortality data to examine 12-month incidence of firearm suicide among emergency department (ED) patients presenting with a range of physical health problems. Participants included all residents presenting to a California ED in 2009-2013 with nonfatal visits for somatic diagnoses hypothesized to increase suicide risk, including myocardial infarction, congestive heart failure, cerebrovascular disease, chronic obstructive pulmonary disease, diabetes, cancer, back pain, headache, joint disorder, and injuries. For each patient diagnostic group, we calculated rates of firearm suicide per 100,000 person-years and standardized mortality ratios (SMRs) relative to the demographically matched California population. RESULTS:Firearm suicide rates per 100,000 person-years ranged from 9.6 (among patients presenting with unintentional injury) to 55.1 (patients with cancer diagnoses), with SMRs from 1.48 to 7.45 (all p<0.05). SMRs for patients with cardiovascular conditions ranged from 2.45 to 5.10. Males and older individuals had higher firearm suicide rates, and there was substantial between-group variability in the proportion of suicide decedents who used a firearm. CONCLUSIONS:ED patients presenting with deliberate self-harm injuries, substance use, and cancer were especially at risk for firearm suicide. To avoid missed suicide-prevention opportunities, EDs should implement evidence-based suicide interventions as a best practice for their patients.

PURPOSE/OBJECTIVE:There are well-established associations between parental/peer relationships and adolescent substance use, but few longitudinal studies have examined whether adolescents change their substance use in response to changes in their parents' behavior or peer networks. We employ a within-person change approach to address two key questions: Are changes in parenting and peer factors associated with changes in adolescent marijuana and alcohol use? Are there sensitive periods when changes in parenting and peer factors are more strongly associated with changes in adolescent marijuana and alcohol use? METHODS:We analyzed longitudinal data collected annually on 503 boys, ages 13-19, recruited from Pittsburgh public schools. Questionnaires regarding parental supervision, negative parenting practices, parental stress, physical punishment, peer delinquency, and peer drug use were administered to adolescents and their caretakers. Alcohol and marijuana use were assessed by a substance use scale adapted from the National Youth Survey. RESULTS:Reductions in parental supervision and increases in peer drug use and peer delinquency were associated with increases in marijuana frequency, alcohol frequency, and alcohol quantity. Increases in parental stress were associated with increases in marijuana and alcohol frequency. The magnitudes of these relationships were strongest at ages 14-15 and systematically decreased across adolescence. These associations were not due to unmeasured stable confounders or measured time-varying confounders. CONCLUSIONS:Reducing or mitigating changes in parenting and peer risk factors in early adolescence may be particularly important for preventing substance use problems as adolescents transition into young adulthood.

BACKGROUND AND AIMS/OBJECTIVE:Debates about lowering the blood alcohol concentration (BAC) limit for drivers are intensifying in the United States and other countries, and the World Health Organization recommends the limit for adults should be 0.05%. In January 2016, Uruguay implemented a law setting zero-BAC limit for all drivers. This aimed to assess the effect of this policy on the frequency of moderate/severe-injury and fatal traffic crashes. DESIGN/METHODS:A quasi experimental study in which a synthetic control model was used with controls consisting of local areas in Chile as the counterfactual for outcomes in Uruguay, matched across population counts and pre-intervention period outcomes. Sensitivity analyses were also conducted. SETTING/METHODS:Uruguay and Chile. CASES/METHODS:Panel data with crash counts by outcome per locality-month (2013-2017). INTERVENTION AND COMPARATOR/UNASSIGNED:A zero-blood alcohol concentration law implemented 9 Jan 2016 in Uruguay, alongside a continued 0.03g/dL BAC threshold in Chile. MEASUREMENTS/METHODS:Per capita moderate/severe injury (i.e., moderate or severe), severe injury, and fatal crashes (2016-2017). FINDINGS/RESULTS:Our base synthetic control model results suggested a reduction in fatal crashes at 12 months (20.9%; p-value=0.018, 95% CI: [-0.340, -0.061]). Moderate-/severe-injury crashes did not decrease significantly (10.2%, p=0.312 [-.282, .075]). The estimated effect at 24 months was smaller and with larger confidence intervals for fatal crashes (14%; p =0.048 [-.246, -.026]) and largely unchanged for moderate/severe-injury crashes (-9.4%, p=.302 [-.248, .075]). Difference-in-differences analyses yielded similar results. As a sensitivity test, a synthetic control model relying on an inferior treatment-control match pre-intervention (measured by mean squared error) yielded similar sized differences that were not statistically significant. CONCLUSIONS:Implementation of a law setting a zero blood-alcohol concentration threshold for all drivers in Uruguay appears to have resulted in a reduction in fatal crashes in the following 12 months and 24 months.