Integrated Treatment of PTSD and Substance Use Disorders: The Mediating Role of PTSD Improvement in the Reduction of Depression

Posttraumatic stress disorder (PTSD) represents one of the most common mental health disorders, particularly among veterans, and is associated with significant distress and impairment. This highly debilitating disorder is further complicated by common comorbid psychiatric disorders, such as substance use disorders (SUD). Individuals with PTSD and co-occurring SUD also commonly present with secondary symptoms, such as elevated depression. Little is known, however, about how these secondary symptoms are related to treatment outcome. The aim of the present study, therefore, was to examine (1) the effects of treatment of comorbid PTSD/SUD on depressive symptoms; and (2) whether this effect was mediated by changes in PTSD severity or changes in SUD severity. Participants were 81 U.S. military veterans (90.1% male) with PTSD and SUD enrolled in a randomized controlled trial examining the efficacy of an integrated, exposure-based treatment (Concurrent Treatment of PTSD and Substance Use Disorders Using Prolonged Exposure; n = 54) versus relapse prevention (n = 27). Results revealed significantly lower depressive symptoms at post-treatment in the COPE group, as compared to the relapse prevention group. Examination of the mechanisms associated with change in depression revealed that reduction in PTSD severity, but not substance use severity, mediated the association between the treatment group and post-treatment depression. The findings underscore the importance of treating PTSD symptoms in order to help reduce co-occurring symptoms of depression in individuals with PTSD/SUD. Clinical implications and avenues for future research are discussed

Genetic associations between alcohol phenotypes and life satisfaction: a genomic structural equation modelling approach

Abstract Alcohol use (i.e., quantity, frequency) and alcohol use disorder (AUD) are common, associated with adverse outcomes, and genetically-influenced. Genome-wide association studies (GWAS) identified genetic loci associated with both. AUD is positively genetically associated with psychopathology, while alcohol use (e.g., drinks per week) is negatively associated or NS related to psychopathology. We wanted to test if these genetic associations extended to life satisfaction, as there is an interest in understanding the associations between psychopathology-related traits and constructs that are not just the absence of psychopathology, but positive outcomes (e.g., well-being variables). Thus, we used Genomic Structural Equation Modeling (gSEM) to analyze summary-level genomic data (i.e., effects of genetic variants on constructs of interest) from large-scale GWAS of European ancestry individuals. Results suggest that the best-fitting model is a Bifactor Model, in which unique alcohol use, unique AUD, and common alcohol factors are extracted. The genetic correlation (r g ) between life satisfaction-AUD specific factor was near zero, the r g with the alcohol use specific factor was positive and significant, and the r g with the common alcohol factor was negative and significant. Findings indicate that life satisfaction shares genetic etiology with typical alcohol use and life dissatisfaction shares genetic etiology with heavy alcohol use

Associations of subjective and objective stress responses with interpersonal trauma, PTSD, stress-induced drinking, and drinking to cope in young adults

Objective: To understand how interpersonal trauma (IPT), stress response, and drinking to cope converge to predict stress-induced drinking, a risk factor for alcohol use disorder. Method: Young adults with no substance use disorder were classified into three trauma history groups: (a) IPT with PTSD (n = 27), (b) IPT without PTSD (n = 35), and (c) Control (no trauma-history/no PTSD; n = 36). Participants completed a baseline assessment, including a structured clinical interview, to confirm PTSD diagnosis, followed by the Trier Social Stressor Task (TSST) and an alcohol use task. Subjective units of distress and blood serum cortisol were collected at standardized timepoints throughout the tasks. Results: In all three groups (PTSD, IPT, control), males consumed more alcohol in the lab than females. Participants in the PTSD group had significantly higher drinking to cope motives, which were associated with greater subjective reactivity; however, neither drinking to cope motives nor subjective reactivity to the TSST predicted post-stressor alcohol consumption for those with PTSD. Conclusions: The interplay among trauma history, stress, and drinking among young adults is nuanced; additional lab-based studies are needed to further clarify the nuanced connection between trauma history, acute stress reactions, and alcohol use

A Longitudinal Mediational Investigation of Risk Pathways among Cannabis Use, Interpersonal Trauma Exposure, and Posttraumatic Stress Disorder

Background: College students are at high risk for cannabis use, interpersonal trauma (IPT) exposure, and posttraumatic stress disorder (PTSD). Two phenotypic etiologic models posited to explain associations between cannabis use and trauma-related phenotypes are the self-medication (trauma/PTSD cannabis use) and high-risk (cannabis use trauma/PTSD) hypotheses. The primary objective of this study was to investigate direct and indirect associations among cannabis use, IPT exposure, and PTSD above and beyond established covariates. Methods: The current study used data from the first assessment (i.e., baseline survey at year 1 Fall) and two follow-up assessments (i.e., year 1 Spring and year 2 Spring) from an ongoing longitudinal study on college behavioral health. Participants were four cohorts of college students (n = 9,889) who completed measures of demographics, substance use, IPT, and PTSD. Indirect effects of IPT on cannabis through PTSD (i.e., self-medication) and cannabis on PTSD through IPT (i.e., high-risk), including tests of covariate effects (e.g., sex, age, race, cohort, alcohol, nicotine) were simultaneously estimated using a longitudinal mediation modeling framework. Results: Results suggest that more IPT exposure increases risk for PTSD and subsequent non-experimental (use 6+ times) cannabis use, and that experimental (use 1 – 5 times) and non-experimental cannabis use increases risk for IPT exposure and subsequent PTSD. Conclusions: Both the self-medication and high-risk hypotheses were supported. Findings support a bidirectional causal relationship between cannabis use and trauma-related phenotypes. Additionally, results highlight areas for colleges to intervene among students to help reduce cannabis use and create a safer environment

A Longitudinal Investigation of Interpersonal Trauma Exposure and Cannabis Use among College Students

Objective: College students have an increased risk for cannabis use and trauma exposure. Cannabis use and trauma exposure have a reciprocal relationship and given the potential negative consequences of both (e.g., poor academic outcomes), there is a need to understand their co-occurring etiology. Two primary etiologic models exist: self-medication (i.e., trauma cannabis use) and high-risk (i.e., cannabis use trauma exposure) hypotheses. The purpose of this study is to investigate the bidirectional relationship between cannabis use and interpersonal trauma (IPT) exposure above and beyond established covariates (e.g., sex, race, alcohol, nicotine). Method: Participants are from an ongoing longitudinal study on college behavioral health at a mid-Atlantic public university (Dick et al., 2014). The present study used data from the first assessment (i.e., baseline survey at year 1 Fall) and one follow-up assessment (i.e., year 1 Spring). Participants were 4 cohorts of college students (n = 9,889) who completed measures of demographic variables, substance use (e.g., cannabis, alcohol, nicotine), and IPT. Associations between cannabis use and IPT and covariates (e.g., sex, race, cohort, alcohol, nicotine) were estimated using cross-lagged path analyses. Results: Results supported the self-medication hypothesis (i.e., IPT cannabis use), but not the high-risk hypothesis (i.e., cannabis use IPT). Alcohol and nicotine use were also significant predictors of both cannabis use and IPT. Conclusions: These findings provide preliminary support for the self-medication hypothesis, indicating that those reporting IPT exposure may be at risk for cannabis use. Implications of these findings, in light of study limitations, are discussed

Unpacking the impact of the COVID-19 pandemic: identifying structural domains

Background: The novel coronavirus-19 (COVID-19) pandemic is a collective crisis that imposed an abrupt and unprecedented impact on college students, as universities were closed with little warning. Paired with the challenges associated with physical distancing (e.g. economic stress, job loss, food insecurity, housing challenges) and the simultaneous need to balance continued and new academic demands, impact will be wide-ranging. It is critical to determine the structure of the impact of this heterogeneous stressor (e.g. health concerns, pandemic worry, financial concerns) for prevention and intervention planning. Objective: Through an existing recruitment pipeline we were in a unique position to study the wide-ranging reach of this pandemic in a cohort of students for whom their university experiences were like no other cohort in history. Method: Data were collected from students who were in their third year of college during the onset of the pandemic; of the N = 1,899 in the cohort who were invited to participate in this COVID-related survey, 897 (47.2%) completed measures of impact between May and July of 2020. Results: A series of confirmatory and exploratory models were fit to examine the structure of the pandemic-related domains. Following estimation of a single-factor model, a correlated five factors model, as well as two second-order factor structures, the five correlated factors (exposure, worry, housing/food instability, social media, substance use) model was found to represent the data most appropriately, while producing an interpretable solution. Conclusions: These measurement model analyses set the stage for future research to examine how these correlated factors impact psychiatric, substance, and academic outcomes in this vulnerable population

Is Pre-College Interpersonal Trauma Associated with Cannabis Use?

Objective: To examine the prevalence and correlates of lifetime cannabis use (i.e., experimental [use 1-5 times] and non-experimental [use ≥ 6 times]) in relation to demographics, interpersonal trauma (IPT), and alcohol and nicotine use. Participants: A large (n = 9,889) representative sample of college students at an urban college campus in the southeastern part of the United States. Methods: Participants were 4 cohorts of first-year college students who completed measures of demographic variables, cannabis, alcohol, nicotine, and IPT. Associations were estimated using multinomial logistic regressions. Results: The prevalence of lifetime cannabis use was 45.5%. Specifically, 28.1% reported non-experimental cannabis use and 17.4% reported experimental cannabis use. Race, cohort, nicotine, and IPT were associated with experimental and non-experimental cannabis use. Additionally, alcohol and sex were associated with non-experimental cannabis use. Conclusions: Results show that cannabis use is prevalent among college students and is associated with race, IPT, and other substance use

Alcohol use and alcohol use disorder differ in their genetic relationships with PTSD: A genomic structural equation modelling approach

PURPOSE: Posttraumatic Stress Disorder (PTSD) is associated with increased alcohol use and alcohol use disorder (AUD), which are all moderately heritable. Studies suggest the genetic association between PTSD and alcohol use differs from that of PTSD and AUD, but further analysis is needed. BASIC PROCEDURES: We used genomic Structural Equation Modeling (genomicSEM) to analyze summary statistics from large-scale genome-wide association studies (GWAS) of European Ancestry participants to investigate the genetic relationships between PTSD (both diagnosis and re-experiencing symptom severity) and a range of alcohol use and AUD phenotypes. MAIN FINDINGS: When we differentiated genetic factors for alcohol use and AUD we observed improved model fit relative to models with all alcohol-related indicators loading onto a single factor. The genetic correlations (rG) of PTSD were quite discrepant for the alcohol use and AUD factors. This was true when modeled as a three-correlated-factor model (PTSD-AUD rG:.36, p < .001; PTSD-alcohol use rG: -0.17, p < .001) and as a Bifactor model, in which the common and unique portions of alcohol phenotypes were pulled out into an AUD-specific factor (rG with PTSD:.40, p < .001), AU-specific factor (rG with PTSD: -0.57, p < .001), and a common alcohol factor (rG with PTSD:.16, NS). PRINCIPAL CONCLUSIONS: These results indicate the genetic architecture of alcohol use and AUD are differentially associated with PTSD. When the portions of variance unique to alcohol use and AUD are extracted, their genetic associations with PTSD vary substantially, suggesting different genetic architectures of alcohol phenotypes in people with PTSD