Exploring predictors of substance use disorder treatment engagement with machine learning: The impact of social determinants of health in the therapeutic landscape.

BACKGROUND: Improved knowledge of factors that influence treatment engagement could help treatment providers and systems better engage patients. The present study used machine learning to explore associations between individual- and neighborhood-level factors, and SUD treatment engagement. METHODS: This was a secondary analysis of the Global Appraisal of Individual Needs (GAIN) dataset and United States Census Bureau data utilizing random forest machine learning and generalized linear mixed modelling. Our sample (N = 15,873) included all people entering SUD treatment at GAIN sites from 2006 to 2012. Predictors included an array of demographic, psychosocial, treatment-specific, and clinical measures, as well as environment-level measures for the neighborhood in which patients received treatment. RESULTS: Greater odds of treatment engagement were predicted by adolescent age and psychiatric comorbidity, and at the neighborhood-level, by low unemployment and high population density. Lower odds of treatment engagement were predicted by Black/African American race, and at the neighborhood-level by high rate of public assistance and high income inequality. Regardless of the degree of treatment engagement, individuals receiving treatment in areas with high unemployment, alcohol sale outlet concentration, and poverty had greater substance use and related problems at baseline. Although these differences reduced with treatment and over time, disparities remained. CONCLUSIONS: Neighborhood-level factors appear to play an important role in SUD treatment engagement. Regardless of whether individuals engage with treatment, greater loading on social determinants of health such as unemployment, alcohol sale outlet density, and poverty in the therapeutic landscape are associated with worse SUD treatment outcomes.

Longitudinal associations between insomnia, cannabis use and stress among US veterans.

Insomnia is highly prevalent among military veterans, with rates nearly double that of civilian populations. Insomnia typically co-occurs with other psychological problems, including substance use (e.g. cannabis) and perceived stress. Much of the research focused on insomnia, stress and cannabis use explores cannabis as a sleep aid and a mechanism for stress relief. However, recent theoretical and empirical evidence suggests a dynamic interplay between insomnia, cannabis use and perceived stress, yet few longitudinal studies exist. Using a sample of 1105 post-9/11 veterans assessed over four time points across 12 months, we used latent difference score modelling to examine proportional change between insomnia, perceived stress and cannabis use. Results revealed a complex interplay between all three constructs. In particular, we show that higher prior levels of insomnia are associated with greater increases in perceived stress, and greater prior levels of stress are associated with greater increases in cannabis use. Perhaps more importantly, our results also point to cannabis use as a catalyst for greater increases in both stress and insomnia severity. Our results suggest there may be both benefits and costs of cannabis use among veterans. Specifically, for veterans who experience chronic sleep problems, perceived stress may become overwhelming, and the benefit of stress reduction from increased cannabis use may come at the cost of increasing insomnia symptomology.

Longitudinal Associations between Homelessness and Substance Use: Investigating Demographic Differences for Young Adults in Treatment.

Objective: To examine prospective, bidirectional associations between homelessness and substance use frequency among young adults receiving substance use treatment in the United States. We also investigated potential differences across demographic subgroups. Methods: Young adults (N = 3717, Mage = 20.1, 28% female, 7.3% sexual/gender minority, and 37% non-Hispanic White) receiving substance use treatment in the U.S. completed assessments at intake, 3 months, 6 months, and 12 months post-intake. Latent growth curve models with structured residuals (LGC-SR) were used to examine cross-lagged associations between homeless days and frequency of substance use and associated problems. Models were stratified by sex, race/ethnicity, and sexual and/or gender minority status. Results: Overall, days spent homeless (µslope= -0.19, p = 0.046) and substance use frequency (µslope1= -6.19, p < 0.001) significantly decreased during treatment, with no significant cross-lagged associations between homeless days and substance use frequency. However, results differed by race and ethnicity. For non-Hispanic White young adults, greater substance use at treatment entry was associated with steeper declines in homeless days between-persons (ϕstandardized = -0.14, p = 0.04). For African Americans, homeless days at treatment entry were associated with greater increases in substance use between-persons (ϕstandardized = 0.29, p = 0.04). No significant differences were found by sex or sexual/gender minority status. Conclusions: Despite overall declines in homelessness and substance use during treatment, these outcomes may unfold differently for non-Hispanic White and African American young adults. More support may be needed for African American young adults reporting homelessness at treatment entry.

Bidirectional Associations Between Pain and Perceived Stress Among Veterans: Depressive Disorder as a Predisposing Factor.

OBJECTIVE: Military veterans who were injured in combat very often report pain along with co-occurring perceived stress and preexisting depressive disorder. The systems model of pain is a theoretical model suggesting that pain and perceived stress are bidirectionally associated at the within-person level, and associations are heightened among those with depressive disorder. However, the systems model of pain has not been adequately tested. Testing the systems model of pain could illuminate salient treatment targets for combat-injured veterans with pain and co-occurring psychological problems. METHODS: The present study empirically tests the systems model of pain among a sample of combat-injured veterans ( N = 902) surveyed five times during an 18-month period. We used a multigroup, autoregressive latent trajectory with structured residual statistical model to test the within-person associations between pain and perceived stress and determine whether associations differ between veterans with and without a positive screen for depressive disorder. RESULTS: In line with the systems model of pain, pain and perceived stress were bidirectionally associated only among combat-injured veterans with depressive disorder. Among such veterans, perceived stress was positively associated with subsequent pain ( b = 0.12; 95% confidence interval = 0.06-0.17), and pain was positively associated with subsequent perceived stress ( b = 0.44; 95% CI = 0.11-0.77). CONCLUSIONS: Our work highlights the interplay between pain and its psychological correlates among a particularly at-risk population. Clinicians addressing pain and perceived stress among combat-injured veterans should be prepared to identify and address depressive disorder.

Longitudinal associations among experiences of sexual assault, posttraumatic stress disorder symptoms, and heavy drinking in young adults.

Prior research with young adults has demonstrated clear associations between experiences of sexual assault, symptoms of posttraumatic stress disorder (PTSD), and alcohol use, but most studies have been cross-sectional or have not considered multiple theoretical pathways to understand these associations. Using six waves of data from a longitudinal cohort sample of 1,719 young adults, we examined associations among experiences of past-year sexual assault (i.e., rape, unwanted sexual touching, and physical intimidation in a sexual way), PTSD symptoms, and the frequency of binge drinking over time, allowing for the exploration of symptom-induced, interpersonal risk, and substance-induced pathways for male and female participants. For both male, ßs = 2.84 to 6.55, and female participants, ßs = 2.96 to 10.1, higher prior levels of PTSD symptoms were associated with larger increases in binge drinking over time. For female participants, higher prior levels of sexual assault were associated with larger increases in PTSD symptoms over time, ßs = 3.48 to 4.25, whereas for male participants, higher prior levels of past-year binge drinking were associated with decreases in PTSD symptoms over time, ßs = -2.75 to -0.53. Continued efforts are needed to prevent sexual assault among young adults and address PTSD symptoms among those who experience sexual assault. Interventions that target binge drinking are also needed for individuals who experience PTSD symptoms, especially young adults, to address potentially hazardous drinking before problems escalate and become chronic.

Rates of Emotional Disturbance Among Children in Foster Care: Comparing Federal Child Welfare Data and Medicaid Records in Two States.

The purpose of this study is to estimate the rate of emotional disturbance (ED) among children in foster care and assess the validity of the national foster care census data (AFCARS) measure of ED. This study used linked child protection and Medicaid records from 2014 and 2015, for the states of California and Wisconsin, as well as data from AFCARS, a federal population census of children in foster care which states are mandated to contribute to. ED is defined by AFCARS and includes an array of mental and behavioral health diagnoses. According to AFCARS, 13% of CA children in foster care and 15% of WI children in foster care had an ED, whereas Medicaid claims produce rates of 45% and 48%, respectively. Rates of ED among children in congregate care were underestimated by 43-46 percentage points, with substantial proportions having diagnoses of disruptive behavioral disorders. Despite the AFCARS ED measure being cited in congressional testimonies and its wide use in research, results from this study suggest that the AFCARS ED estimates are an unreliable metric for use in research, policy, or practice.

Directional associations between posttraumatic stress disorder symptoms and cannabis use in young adults: Uncovering variation by sex, race, and ethnicity.

OBJECTIVE: Prevalence rates of cannabis use and PTSD vary, with men reporting greater cannabis use than females, females reporting higher rates of PTSD than males, and race and ethnic minority persons reporting higher rates of both cannabis and PTSD compared to non-Hispanic White individuals. This study extends our understanding of directional associations between cannabis use and PTSD from early to late young adulthood (18-26 years old) using two theoretical models: symptom-driven pathway and substance-induced pathway. METHOD: Participants provided yearly data for 14 years, and the present study utilized data from Waves 9 through 14. Those endorsing Criterion A in at least one wave of data collection (n = 1,454) were included in the analytic sample. We used autoregressive latent trajectory with structured residuals to understand reciprocal associations for the full sample, as well as by sex and race or ethnicity. RESULTS: For the full sample, we noted support for both symptom-driven and substance-induced pathways during early young adulthood (18-20) but only support for a symptom-driven pathway during late young adulthood (21-26). Males showed the same pattern as the full sample; however, for females, only a symptom-driven pathway during late young adulthood was found. For race and ethnic minority participants, we showed full cross-lagged effects during both early and late young adulthood and no associations for non-Hispanic White individuals. CONCLUSIONS: Results indicate that both men and individuals from minoritized racial and ethnic groups are more likely to report heightened PTSD symptomology, maladaptive coping, and worsening symptoms. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

An open-source probabilistic record linkage process for records with family-level information: Simulation study and applied analysis.

Research with administrative records involves the challenge of limited information in any single data source to answer policy-related questions. Record linkage provides researchers with a tool to supplement administrative datasets with other information about the same people when identified in separate sources as matched pairs. Several solutions are available for undertaking record linkage, producing linkage keys for merging data sources for positively matched pairs of records. In the current manuscript, we demonstrate a new application of the Python RecordLinkage package to family-based record linkages with machine learning algorithms for probability scoring, which we call probabilistic record linkage for families (PRLF). First, a simulation of administrative records identifies PRLF accuracy with variations in match and data degradation percentages. Accuracy is largely influenced by degradation (e.g., missing data fields, mismatched values) compared to the percentage of simulated matches. Second, an application of data linkage is presented to compare regression model estimate performance across three record linkage solutions (PRLF, ChoiceMaker, and Link Plus). Our findings indicate that all three solutions, when optimized, provide similar results for researchers. Strengths of our process, such as the use of ensemble methods, to improve match accuracy are discussed. We then identify caveats of record linkage in the context of administrative data.

Caseworker documentation of mothers in foster care: A case study in California.

BACKGROUND: Young people in foster care frequently experience early parenting, and U.S. law requires the documentation of parents in care. The extent to which the child protection system (CPS) has accurately collected information on parents in care remains largely unknown and has ramifications for the planning and delivery of services. OBJECTIVE: Using California as a case study, this study documented young mothers in care using birth records, determined the proportion of mothers correctly identified in CPS records, and compared characteristics and placements of mothers who were or were not identified. POPULATION: All mothers aged 15-21 years documented by vital birth records (2014 and 2019) were probabilistically linked to CPS records, yielding 3199 mothers in care. METHOD: We compared mothers who were or were not identified in CPS records using bivariate statistics. A chi-square test for trends examined differences in documentation over time. RESULTS: A third of mothers were not identified as such in CPS records (n = 1136). The proportion of mothers identified by caseworkers rose from 50 % in 2014 to 71.5 % in 2019 (p < .001). Nonminor dependent mothers and those placed in supervised independent living programs were more likely to be misclassified in CPS data. CONCLUSIONS: Motherhood may not be documented in CPS records; however, significant improvements were evident. Results suggest that all nonminor dependents should be informed of available services for expectant and parenting individuals, especially if they are living in less restrictive placements, given they are more likely to give birth and less likely to be identified in CPS records than minor dependents.

High Spirits? Exploring "Halloweekend" Alcohol and Cannabis Use Among Heavy-Drinking College Students.

OBJECTIVE: Specific events are associated with heavier and riskier substance use behaviors among college students, including holidays like Halloween, which may include several days of themed parties/events ("Halloweekend"). The current study compared drinking, pregaming (i.e., fast-paced drinking before going out for the night), cannabis use, same-day alcohol and cannabis co-use, and negative alcohol-related consequences over Halloweekend compared with two adjacent non-Halloween weekends among a sample of heavy-drinking university students. METHOD: Participants (N = 228; 65% female) provided 28 days of daily diary data. We used a three-level generalized linear mixed model (GLMM) approach estimating zero-inflated Conway-Maxwell Poisson regressions to assess the effect of weekend and specific weekend day on number of overall drinks, number of pregaming drinks, and negative alcohol-related consequences. Proportions tests assessed for differences in any cannabis use and daily co-use between Halloweekend and non-Halloween weekends. RESULTS: Zero-inflated portions of the GLMMs indicated that general drinking, pregaming, and negative consequences were most prevalent on Halloweekend and Fridays and Saturdays. Count portions of the models indicated that general drinking quantity was highest during these periods, and participants experienced a greater number of negative consequences on Halloweekend compared with the weekend before; no differences were observed in the quantity of pregaming drinks consumed across weekends or days. No significant differences in cannabis use or co-use were observed between weekends. CONCLUSIONS: Given risk associated with Halloweekend compared with weekends immediately before and after, interventions targeting alcohol use and pregaming on Halloweekend may be beneficial to reduce related harm for heavy-drinking students.

Changes in Household Challenges and Subsequent Child Welfare Report.

INTRODUCTION: Preventing child maltreatment and reducing adverse childhood experiences is critical for improving adult health. To inform prevention efforts, it is necessary to move beyond static risk models and instead model the dynamic changes in household challenges during the prebirth and early childhood periods. This study examined the effect of changes in the number of household challenges from prebirth (12 months before birth of a child) to early childhood (3 years after birth) period on the risk of a child maltreatment report by age 3 years. METHODS: This retrospective cohort study linked data from the Alaska 2009-2011 Pregnancy Risk Assessment Monitoring System, its 3-year follow-up survey, and administrative records through 2019. Participants were 1,699 birthing parents. Latent class analyses identified prebirth and early childhood low- and high-challenge respondent groups on the basis of the level of reported household challenges. The authors then modeled the relationships between group transition membership and the risk of maltreatment using latent transition analysis. Analyses were conducted in 2021. RESULTS: Households transitioning from a high-challenge-prebirth status to a low-challenge-early-childhood status had a lower predicted risk for child services report than households remaining in the high-challenges group. Transitioning from low- to high-challenges status predicted the highest risk for child services report than that of all other groups. CONCLUSIONS: To reduce the risk of child maltreatment and subsequent adverse childhood experiences, healthcare providers should screen parents for the presence of household challenges during both pregnancy and early childhood and connect patients to resources targeted at reducing those challenges and providing continuous familial support.

Directional associations between cannabis use and depression from late adolescence to young adulthood: the role of adverse childhood experiences.

BACKGROUND AND AIMS: Although the co-occurrence of cannabis and depression is well established, less is known about the temporal sequence of cannabis use and depression. The present study had three main aims: to test a symptom-driven pathway in which depression may drive increases in cannabis use, to test a substance-induced pathway in which cannabis use may drive increases in depression and to assess a shared vulnerability model assessing associations between individuals who have (and have not) experienced adverse childhood experiences (ACEs). DESIGN: Data are from an ongoing, longitudinal, cohort study (n = 2234). Data were set up in an accelerated longitudinal design from age 17 to 24 years. SETTING: Initial sample was recruited from Southern California, USA. The majority of participants still live in Southern California. PARTICIPANTS: On average, participants were aged 18 years at wave 8, with more than half identifying as female (54.3%; n = 1350). Most participants identified as Hispanic (1127; 45.4%), followed by non-Hispanic white (510; 20.5%), Asian (503; 20.2%), multi-racial/other (284; 11.4%) and non-Hispanic black (60; 2.2%). MEASUREMENTS: Primary outcomes were past-month days of cannabis use and depression symptoms [patient health questionnaire (PHQ)-8]. The Adverse Childhood Experiences scale was used as our main grouping measure. FINDINGS: In the full sample, we showed that prior levels of depression symptoms were associated with a decrease in cannabis use [opposite to the proposed symptom driven model; B = -0.33 (-0.58, -0.09)]. Dynamic coupling parameters noted individuals who evidenced greater increases in cannabis use between two prior ages reported greater increases in depressive symptoms between subsequent ages [support for a substance-induced pathway; B = 0.53 (0.18, 0.89)]. Similar to the overall sample, for those who had not experienced ACEs, as cannabis use increased we saw a steady increase in depression [support for a substance induced pathway; B = 0.14 (0.04, 0.29)]. However, for those who experienced ACEs, as cannabis use increased we saw a consistent decrease in depression [opposite to the proposed substance-induced pathway; B = -0.18 (-0.28, -0.08)]. CONCLUSION: There is mixed support for both symptom-driven and substance-induced pathways between cannabis use and depression.

Predictors of Maternal Recidivism in the Child Protection System.

Child maltreatment recidivism is typically measured and studied at the individual level. Conditions that give rise to child abuse and neglect, however, typically affect multiple children in a given family. In the current study, we estimated maltreatment recidivism at the maternal level and examined its risk as a function of maternal sociodemographic characteristics that may change over time. Using linked administrative records, we identified a subset of first-time mothers in California whose first child was reported to the child protection system (CPS) between birth and age 5 and who then gave birth to another child (n = 14,715). Following the firstborn child's CPS reporting, nearly half of these mothers (43.3%) were re-reported concerning the non-firstborn children during the first 5 years of the child's life. Risk factors consistently documented across births were associated with a heightened risk of maternal CPS recidivism. Our study advances an understanding of the full extent of maltreatment recidivism by broadening the focus from individual children.

General cognitive ability assessment in the German National Cohort (NAKO) - The block-adaptive number series task.

Objectives. Evaluate the block-adaptive number series task of reasoning, as a time-efficient proxy of general cognitive ability in the Level-2 sample of the German National Cohort (NAKO), a population-based mega cohort.Methods. The number series task consisted of two blocks of three items each, administered as part of the touchscreen-based assessment. Based on performance on the first three items, a second block of appropriate difficulty was automatically administered. Scoring of performance was based on the Rasch model. Relations of performance scores to age, sex, education, study centre, language proficiency, and scores on other cognitive tasks were examined.Results. Except for one very difficult item, the data of the remaining 14 items showed sufficient fit to the Rasch model (Infit: 0.89-1.04; Outfit: 0.80-1.08). The resulting performance scores (N = 21,056) had a distribution that was truncated at very high levels of ability. The reliability of the performance estimates was satisfactory. Relations to age, sex, education, and the executive function factor of the other cognitive tasks in the NAKO supported the validity.Conclusions. The number series task provides a valid proxy of general cognitive ability for the Level-2 sample of the NAKO, based on a highly time-efficient assessment procedure.

Childhood adversity, combat experiences, and military sexual trauma: a test and extension of the stress sensitization hypothesis.

BACKGROUND: U.S. veterans report high rates of traumatic experiences and mental health symptomology [e.g. posttraumatic stress disorder (PTSD)]. The stress sensitization hypothesis posits experiences of adversity sensitize individuals to stress reactions which can lead to greater psychiatric problems. We extend this hypothesis by exploring how multiple adversities such as early childhood adversity, combat-related trauma, and military sexual trauma related to heterogeneity in stress over time and, subsequently, greater risk for PTSD. METHODS: 1230 veterans were recruited for an observational, longitudinal study. Veterans responded to questionnaires on PTSD, stress, and traumatic experiences five times over an 18-month study period. We used latent transition analysis to understand how heterogeneity in adverse experiences is related to transition into stress trajectory classes. We also explored how transition patterns related to PTSD symptomology. RESULTS: Across all models, we found support for stress sensitization. In general, combat trauma in combinations with other types of adverse experiences, namely early childhood adversity and military sexual trauma, imposed a greater probability of transitioning into higher risk stress profiles. We also showed differential effects of early childhood and military-specific adversity on PTSD symptomology. CONCLUSION: The present study rigorously integrates both military-specific and early life adversity into analysis on stress sensitivity, and is the first to examine how sensitivity might affect trajectories of stress over time. Our study provides a nuanced, and specific, look at who is risk for sensitization to stress based on previous traumatic experiences as well as what transition patterns are associated with greater PTSD symptomology.

A Population-Based Study of Mental Health Diagnoses and Child Protection System Involvement Among Medicaid-Insured Children.

OBJECTIVE: To determine the population prevalence of diagnosed mental health disorders among Medicaid-insured children <18 years old in California based on levels of current and past child protection system (CPS) involvement. STUDY DESIGN: In this retrospective, population-based study, we examined the full population of children enrolled in California's Medicaid program for at least 1 month between 2014 and 2015 and who had at least 1 claim during that period (n = 3 352 886). Records for Medicaid-insured children were probabilistically linked to statewide CPS records of maltreatment and foster care placements since 1998. A primary or secondary mental health diagnosis was classified using International Classification of Diseases codes. RESULTS: Overall, 14% (n = 470 513) of all children insured through Medicaid in 2014-2015 had a documented mental health diagnosis. Among children with a diagnosis, the percentage with CPS involvement (ie, any report for maltreatment) was nearly twice that of the Medicaid population overall (50.4% vs 26.9%). This finding held across all diagnostic groups but with notable variations in magnitude. A graded relationship emerged between the level of CPS involvement and the likelihood of a mental health diagnosis. Diagnoses among children reported for maltreatment were common, regardless of placement in foster care. CONCLUSIONS: Findings document high rates of both mental health diagnoses and past child protection involvement in a population of Medicaid-insured children. Most children reported for maltreatment will never be placed in foster care, underscoring the importance of ensuring that the children who remain at home receive the proper array and coordination of services.

Directional associations between cannabis use and anxiety symptoms from late adolescence through young adulthood.

BACKGROUND: Two major theories aid in explaining the association between anxiety and cannabis use: a symptom-driven pathway (heightened anxiety precedes greater cannabis use) and a substance-induced pathway (greater use precedes heightened anxiety). Although the co-occurrence of cannabis use and anxiety symptomology is well-established, less is known about the temporal sequence of cannabis use and anxiety symptomology over the course of young adult development METHODS: Data are from an ongoing, longitudinal, cohort study. All prospective analyses used data from wave 8, when participants were between the ages of 17 and 20, through wave 13, when participants are between ages 21 and 24 (N = 2995). Data were set up in accelerated longitudinal design in which we estimated a series of latent difference score models between anxiety and cannabis use from 17 to 24 years old. Models were estimated for men and women, separately. RESULTS: For the overall sample and men, greater cannabis use predicted greater subsequent increases in anxiety; however, greater anxiety symptoms were associated with decreasing cannabis use. For women, results were more complex. A positive association was noted between prior, trait-like levels of anxiety predicting greater change (increasing) in anxiety symptomology. However, when change is predicted by prior change we see that cannabis use decreases among women who have recently experienced an increase in anxiety CONCLUSION: The nuanced set of results from this study support a dynamic interplay between anxiety symptoms and cannabis use, with important sex differences observed. Overall, our results pave the way for rethinking our guiding theories to include a more robust, flexible, and dynamic model for understanding associations between substance use and mental health symptomology during a key period of development.

What's sleep got to do with it? Longitudinal associations between insomnia, PTSD, and alcohol use among U.S. Veterans.

U.S. veterans are at risk for insomnia, which often co-occurs with symptoms of posttraumatic stress disorder (PTSD) and alcohol use. Much of the research on veterans and these three constructs is cross-sectional and focused on unidirectional pathways. Recent theoretical and empirical evidence suggests a dynamic interplay between insomnia, PTSD, and alcohol use, yet few longitudinal studies exist. A clearer understanding of these pathways is needed to help inform integrated treatments. Using a sample of 1,230 post-9/11 veterans assessed over four time points across 12 months, we used a latent difference score modeling approach to examine proportional and dynamic change between insomnia, PTSD, and alcohol. Results revealed a complex interplay between all three constructs. Higher prior levels of both PTSD and alcohol use were associated with greater subsequent changes in insomnia symptoms (i.e., worse sleep). Moreover, although veterans drank less frequently as their insomnia symptoms worsened over time, greater changes in insomnia symptoms (i.e., worse symptoms) was a mechanism linking PTSD and more frequent drinking. As the research on interventions addressing insomnia, PTSD, and alcohol is limited, there are opportunities for researchers and clinicians to develop programs that effectively target all three in integrated treatments.

Changes in perceived stress during the COVID-19 pandemic among American veterans.

American veterans are a population that suffer from both context specific stressors as well as many population-specific major-life events. The present exploratory study utilises a longitudinal cohort of 1230 U.S. veterans surveyed from February 2020 through February 2021. We sought to understand heterogeneity in perceived stress, using growth mixture modelling, over this time period, how COVID-specific factors such as negative reactions to the pandemic, loneliness, and employment disruptions influence perceived stress trajectories, and how veterans vary across distal outcomes including posttraumatic stress disorder (PTSD), pain, depression, sleep problems, physical health, and alcohol use disorder. Results revealed a 4-class solution: Stable High, Stable Low, Steady Increasing, and Steady Decreasing classes. In terms of COVID specific factors, negative reactions to COVID were consistently associated with perceived stress for those in the Stable High and Steady Increasing classes whereas loneliness was associated with stress trajectories for all emergent classes. Finally, in terms of our distal outcomes, results showed a relatively robust pattern with veterans in the Stable High or Steady Increasing classes reporting worse scores across all outcomes including PTSD, pain, sleep problems, physical health, depression, and alcohol use disorder. Understanding the interplay between existing vulnerabilities, ongoing stressors, and behavioural health outcomes among veterans is crucial for prevention and intervention efforts.

Identifying individual and environmental predictors of opioid and psychostimulant use among adolescents and young adults following outpatient treatment.

BACKGROUND: The United States (US) continues to grapple with a drug overdose crisis. While opioids remain the main driver of overdose deaths, deaths involving psychostimulants such as methamphetamine are increasing with and without opioid involvement. Recent treatment admission data reflect overdose fatality trends suggesting greater psychostimulant use, both alone and in combination with opioids. Adolescents and young adults are particularly vulnerable with generational trends showing that these populations have particularly high relapse rates following treatment. METHODS: We assessed demographic, psychosocial, psychological comorbidity, and environmental factors (percent below the poverty line, percent unemployed, neighborhood homicide rate, population density) that confer risk for opioid and/or psychostimulant use following substance use disorder treatment using two complementary machine learning approaches-random forest and least absolute shrinkage and selection operator (LASSO) modelling-with latency to opioid and/or psychostimulant as the outcome variable. RESULTS: Individual level predictors varied by substance use disorder severity, with age, tobacco use, criminal justice involvement, race/ethnicity, and mental health diagnoses emerging at top predictors. Environmental variabels including US region, neighborhood poverty, population, and homicide rate around patients' treatment facility emerged as either protective or risk factors for latency to opioid and/or psychostimulant use. CONCLUSIONS: Environmental variables emerged as one of the top predictors of latency to use across all levels of substance use disorder severity. Results highlight the need for tailored treatments based on severity, and implicate environmental variables as important factors influencing treatment outcomes.