Browsing by Author "Bountress, Kaitlin E."

Now showing 1 - 7 of 7
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    Alcohol Use and Alcohol Use Disorder Differ in their Genetic Relationships with PTSD: A Genomic Structural Equation Modelling Approach
    (Elsevier, 2022) Bountress, Kaitlin E.; Brick, Leslie A.; Sheerin, Christina; Grotzinger, Andrew; Bustamante, Daniel; Hawn, Sage E.; Gillespie, Nathan; Kirkpatrick, Robert M.; Kranzler, Henry; Morey, Rajendra; Edenberg, Howard J.; Maihofer, Adam X.; Disner, Seth; Ashley-Koch, Allison; Peterson, Roseann; Lori, Adriana; Stein, Dan J.; Kimbrel, Nathan; Nievergelt, Caroline; Andreassen, Ole A.; Luykx, Jurjen; Javanbakht, Arash; Youssef, Nagy A.; Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group; Amstadter, Ananda B.; Biochemistry and Molecular Biology, School of Medicine
    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.
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    Associations among Impulsivity, Trauma History, and Alcohol Misuse within a Young Adult Sample
    (Elsevier, 2017) Bountress, Kaitlin E.; Adams, Zachary W.; Gilmore, Amanda K.; Amstadter, Ananda B.; Thomas, Suzanne; Danielson, Carla Kmett; Psychiatry, School of Medicine
    Objective: Young adult alcohol misuse is associated with numerous long-term adverse outcomes. Given the link between impulsivity and alcohol use, we examined whether three impulsivity-related traits differentially predicted number of drinks per drinking day (DDD). We also examined whether these effects varied for those with different trauma histories. Method: The current study (n=254) examined motor, non-planning, and attentional impulsivity as predictors of DDD. It also examined whether impulsivity was differentially predictive of DDD across individuals in: a control group (non-trauma exposed), a trauma exposed but non-PTSD group, and a PTSD group. Results: Regardless of group, more motor impulsivity was associated with more DDD. The effect of non-planning impulsivity varied according to trauma history. Specifically, more non-planning impulsivity predicted more DDD for those without PTSD. Finally, attentional impulsivity was not predictive of DDD. Conclusions: Young adults with high levels of motor impulsivity, regardless of trauma history, may be a particularly high-risk group in terms of propensity for alcohol use/misuse. Additionally, high levels of non-planning impulsivity may signify those at greater risk for alcohol misuse, among those without PTSD. Motor impulsivity and non-planning impulsivity may serve as useful intervention targets in alcohol misuse prevention efforts. Implications for future research in this area are discussed.
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    Associations of subjective and objective stress responses with interpersonal trauma, PTSD, stress-induced drinking, and drinking to cope in young adults
    (American Psychological Association, 2021) Danielson, Carla Kmett; Hahn, Austin M.; Bountress, Kaitlin E.; Adams, Zachary W.; Calhoun, Casey; Amstadter, Ananda B.; Thomas, Suzanne; Psychiatry, School of Medicine
    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.
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    Depressive symptoms, avoidant coping, and alcohol use: differences based on gender and posttraumatic stress disorder in emerging adults
    (Springer, 2024) Danielson, Carla Kmett; Hahn, Austin M.; Bountress, Kaitlin E.; Gilmore, Amanda K.; Roos, Lydia; Adams, Zachary W.; Kirby, Charli M.; Amstadter, Ananda B.; Psychiatry, School of Medicine
    Trauma exposure and alcohol use often co-occur. Unveiling predictors of drinking behavior, including among those with varying levels of trauma exposure, can inform behavioral health prevention and treatment efforts in at-risk populations. The current study examined associations between depressive symptoms, avoidant coping, gender, and alcohol use among emerging adults with and without trauma exposure and posttraumatic stress disorder (PTSD). Participants were 238 emerging adults between the ages of 21 and 30 years (M = 24.75; SD = 2.61) in one of three groups: trauma-exposed with PTSD (n = 70); trauma-exposed with no PTSD (n = 83); or a no trauma (control) group (n = 85). Demographics, parental alcohol problems, depressive symptoms, and avoidant coping were examined as predictors of drinks per drinking day. Chi-square, t-test, bivariate, and group path analysis were conducted. Among participants, men consumed greater amounts of alcohol than women across all three groups. Group assignment based on trauma history and PTSD significantly moderated the association between avoidant coping and alcohol use such that avoidant coping had a significant effect on alcohol use among participants in the trauma-exposed and PTSD groups. There was also a significant group × gender × avoidant coping interaction such that, among participants in the control group, men had attenuated alcohol use at low levels of avoidant coping and increased at high levels of avoidant coping. No effects of race were observed. Results highlight the importance of avoidant coping as a risk factor for problematic drinking, unveiling a specific intervention target for reducing co-occurring PTSD and problematic alcohol use.
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    Gene Expression Differences Between Young Adults Based on Trauma History and Post-traumatic Stress Disorder
    (Frontiers Media, 2021-04-08) Bountress, Kaitlin E.; Vladimirov, Vladimir; McMichael, Gowon; Taylor, Z. Nathan; Hardiman, Gary; Chung, Dongjun; Adams, Zachary W.; Kmett Danielson, Carla; Amstadter, Ananda B.; Psychiatry, School of Medicine
    Background: The purpose of this study was to identify gene expression differences associated with post-traumatic stress disorder (PTSD) and trauma exposure (TE) in a three-group study design comprised of those with and without trauma exposure and PTSD. Methods: We conducted gene expression and gene network analyses in a sample (n = 45) composed of female subjects of European Ancestry (EA) with PTSD, TE without PTSD, and controls. Results: We identified 283 genes differentially expressed between PTSD-TE groups. In an independent sample of Veterans (n = 78) a small minority of these genes were also differentially expressed. We identified 7 gene network modules significantly associated with PTSD and TE (Bonferroni corrected p ≤ 0.05), which at a false discovery rate (FDR) of q ≤ 0.2, were significantly enriched for biological pathways involved in focal adhesion, neuroactive ligand receptor interaction, and immune related processes among others. Conclusions: This study uses gene network analyses to identify significant gene modules associated with PTSD, TE, and controls. On an individual gene level, we identified a large number of differentially expressed genes between PTSD-TE groups, a minority of which were also differentially expressed in the independent sample. We also demonstrate a lack of network module preservation between PTSD and TE, suggesting that the molecular signature of PTSD and trauma are likely independent of each other. Our results provide a basis for the identification of likely disease pathways and biomarkers involved in the etiology of PTSD.
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    Impulsivity and Comorbid PTSD-Binge Drinking
    (Taylor & Francis, 2018) Walker, Jesse; Bountress, Kaitlin E.; Calhoun, Casey D.; Metzger, Isha W.; Adams, Zachary; Amstadter, Ananda; Thomas, Suzanne; Danielson, Carla Kmett; Psychiatry, School of Medicine
    Objective: Trauma exposure is common, with estimates of 28% to 90% of adults reporting at least one traumatic event over their lifetime. Those exposed to traumatic events are at risk for alcohol misuse (i.e., binge drinking), posttraumatic stress disorder (PTSD), or both. A potential underlying mechanism for this comorbidity is increased impulsivity-the tendency to act rashly. Little work to date has examined the impact of different impulsogenic traits on this comorbidity. Methods: This study (n = 162) investigated trauma-exposed young adults (aged 21-30) who had endorsed a lifetime interpersonal trauma. In addition, three impulsogenic traits (motor, nonplanning, and attentional) were measured. Results: Over and above the covariates for age, gender, race, and traumatic events, greater attentional impulsivity was associated with greater likelihood of meeting criteria for PTSD and binge drinking, compared to meeting criteria for PTSD, binge drinking, or neither. Neither nonplanning impulsivity nor motor impulsivity exerted unique effects. Conclusions: Young adults who report difficulty attending to immediate stimuli within their environment may be unable to think about and/or process the traumatic event, potentially increasing risk for PTSD and maladaptive coping skills to manage this distress (e.g., alcohol misuse, binge drinking).
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    Potential causal effect of posttraumatic stress disorder (PTSD) on alcohol use disorder and alcohol consumption in individuals of European descent: A Mendelian Randomization Study
    (Wiley, 2021) Bountress, Kaitlin E.; Wendt, Frank; Bustamante, Daniel; Agrawal, Arpana; Webb, Bradley; Gillespie, Nathan; Edenberg, Howard; Sheerin, Christina; Johnson, Emma; The Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group; Polimanti, Renato; Amstadter, Ananda; Biochemistry and Molecular Biology, School of Medicine
    Background: Posttraumatic stress disorder (PTSD) often co-occurs with alcohol consumption (AC) and alcohol use disorder (AUD). However, it is unknown whether the same etiologic influences that underlie PTSD co-occurring with AUD are those that underlie PTSD and AC individually. Methods: This study used large-scale genome-wide association study (GWAS) data to test whether PTSD and drinks per week [DPW]/AUD are causally related to one another, and, if so, whether PTSD precedes DPW/AUD and/or vice versa. We used Mendelian Randomization methods to analyze European ancestry GWAS summary statistics from the Psychiatric Genomics Consortium (PGC; PTSD), GWAS & Sequencing Consortium of Alcohol and Nicotine Use (GSCAN; DPW), and the Million Veteran Program (MVP; AUD). Results: PTSD exerted a potentially causal effect on AUD (β = 0.039, SE = 0.014, p = 0.005), but not on DPW (β = 0.002, SE = 0.003, p = 0.414). Additionally, neither DPW (β = 0.019, SE = 0.041, p = 0.637) nor AUD (β = 8.87 × 10-4 , SE = 0.001, p = 0.441) exerted a causal effect on PTSD. Conclusions: These findings are consistent with the self-medication model, in which individuals misuse alcohol to cope with aversive trauma-related symptoms. These findings extend latent analysis and molecular findings of shared and correlated risk between PTSD and alcohol phenotypes. Given the health behaviors associated with these phenotypes, these findings are important in that they suggest groups to prioritize for prevention efforts. Further, they provide a rationale for future preclinical and clinical studies examining the biological mechanisms by which PTSD may impact AUD.