Health correlates of experiential and behavioral avoidance among trauma-exposed veterans.

INTRODUCTION: Avoidance is a well-documented risk factor for poor mental and physical health outcomes. However, limited research has explored this relationship specifically among trauma-exposed veterans, a population known to be particularly prone to avoidance behavior. Conceptually, avoidance is often divided into two distinct but overlapping constructs - experiential avoidance (resisting distressing internal states) and behavioral avoidance (avoiding or changing experiences that elicit distress). In this exploratory survey study, we examined associations between behavioral and experiential avoidance and mental, physical, and cognitive functioning, as well as quality of life. METHODS: Veterans with a trauma history (N = 89) completed a 121-item survey containing validated assessments to examine several mental and physical health and wellness-related variables. Correlations between experiential avoidance and outcome measures, and behavioral avoidance and outcome measures, were explored. Multivariable linear regression analyses were conducted to explore the association between experiential and behavioral avoidance on mental health outcomes. In addition, we conducted exploratory analyses in which we investigated these correlations in those who screened positive for PTSD versus those who did not, and between different types of behavioral avoidance and major outcomes. RESULTS: Experiential avoidance was moderately correlated with distress from depressive symptoms, distress related to past trauma, and health-related and cognitive dysfunction. Experiential Avoidance was weakly correlated with distress from anxiety symptoms and poorer quality of life. Behavioral avoidance was moderately correlated with distress from depressive and anxiety symptoms, distress related to past trauma, and cognitive dysfunction, and was weakly correlated with health-related dysfunction and poorer quality of life. Results from multivariable analyses revealed that experiential avoidance was associated with greater distress related to depressive symptoms and past trauma, and behavioral avoidance was associated with greater distress related to anxiety symptoms, depressive symptoms, and past trauma. CONCLUSIONS: Results suggest that avoidance negatively influences major domains of mental and physical health as well as functioning and health-related quality of life in trauma-exposed veterans. They further indicate that behavioral and experiential avoidance may be differentially linked to mental health outcomes. The results support the idea that avoidance may be an important marker for psychosocial functioning and may serve as a treatment target in trauma-exposed veterans.

Associations Between Childhood Trauma and Tobacco Use Outcomes in Adults after Overnight Abstinence.

INTRODUCTION: Childhood trauma is known to be associated with nicotine dependence, yet limited smoking outcomes have been examined and few studies have assessed associations between specific trauma subscales and smoking. Additionally, sex differences in trauma-smoking relations are understudied. This study examined associations between childhood trauma and several smoking-related outcomes in adults who smoke after overnight abstinence. AIMS AND METHODS: People who smoke (N = 205) completed self-report and biochemical assessments evaluating childhood trauma, affect, nicotine dependence, smoking urges, withdrawal, and plasma cortisol and cotinine levels. Smoking outcomes were compared between those with and without a history of moderate to severe childhood trauma among the total sample and by sex. RESULTS: Relative to those with no to minimal abuse, those with moderate to severe abuse had higher negative affect, withdrawal severity, and plasma cotinine levels. Exploratory analyses revealed that women were more likely than men to have urges to smoke for negative reinforcement and have higher withdrawal severity, but no interactions between abuse group and sex were observed. Examining specific trauma subscales, the moderate to severe emotional abuse group had more severe nicotine dependence, negative affect, and withdrawal compared to the no to minimal group. The moderate to severe sexual abuse group had more severe nicotine dependence and withdrawal compared to the no to minimal group. CONCLUSIONS: Exposure to childhood trauma is associated with more severe nicotine dependence, negative affect, withdrawal, and higher plasma cotinine levels. Findings also indicate that different types of trauma may differentially affect smoking behaviors. IMPLICATIONS: This study of adults who smoke finds that childhood trauma history may be a marker for smoking susceptibility and suggests that individuals with experiences of emotional and sexual abuse may require targeted forms of smoking cessation interventions. Moreover, findings suggest that smoking risks may differ for men and women. Findings inform public health interventions intended to reduce cigarette use in individuals with exposure to childhood trauma.

Examining racial differences in smoking outcomes among smokers enrolled in an intravenous nicotine infusion study.

INTRODUCTION: Large racial disparities exist in the prevention and treatment of smoking-related diseases, and minoritized populations carry a heavier burden of smoking-related morbidity and mortality. To date, most studies investigating smoking-related illnesses have been conducted in samples in which the majority, or totality, self-identified as White or Caucasian. While Black individuals who smoke tend to have a lower rate of nicotine clearance, in part due to the use of mentholated cigarettes, less is known about how slower clearance affects their acute subjective and physiologic responses in response to either overnight abstinence or subsequent nicotine administration. This study aimed to investigate differences between the experiences of Black and White individuals who smoke across these outcomes after a period of short-term abstinence and after IV nicotine infusion. METHODS: The study included 206 smokers (N = 103 Black, N = 103 White, by self-report). The study investigated self-report, physiological, and biochemical smoking-related outcomes following confirmed overnight abstinence followed by IV nicotine infusion. The outcome measures were separately analyzed with repeated-measures mixed-models. RESULTS: Black individuals had lower rates of nicotine clearance and were more likely to smoke mentholated cigarettes than White individuals. Despite these differences, no differences in withdrawal, cravings, or physiological outcomes were observed between the two groups. There were some trends toward differences in subjective experiences, in that an interaction with trend level significance between race and dose was observed for negative subjective drug effects, with White smokers trending towards endorsing higher levels of negative affect after abstinence and nicotine infusion. We also observed that Black individuals trended towards experiencing more negative drug effects in response to initial nicotine delivery than to saline, whereas White individuals had no differences in negative drug effects across saline or nicotine doses. CONCLUSIONS: Despite slower nicotine clearance, Black participants exhibited withdrawal and urges to smoke as severe as White participants, and did not have blunted physiological responses to overnight abstinence or administration of nicotine, which were contrary to our hypotheses. Our findings suggest minimal differences across races in the acute pharmacologic effects of nicotine. We observed trend-level differences in subjective and affective responses to nicotine. Greater insight into these differences may lead to improved prevention and treatment strategies for smoking-related illnesses for Black individuals who smoke.

A systematic review evaluating PTSD treatment effects on intermediate phenotypes of PTSD.

OBJECTIVE: Although the efficacy of evidence-based treatments for posttraumatic stress disorder (PTSD) has been well established, high rates of treatment dropout and/or nonresponse or under-response to treatment suggest a need to explore novel treatment approaches. Most current research has focused on DSM-based categorical outcomes as primary indicators of treatment response, which may obscure the phenotypic heterogeneity of PTSD and limit the ability to map symptoms to underlying neurobiology. This systematic review aimed to identify intermediate phenotypes (IPs) of PTSD and evaluate IP sensitivity to PTSD treatments. METHOD: Five databases were searched for empirical studies published in English between January 1, 2010 and August 1, 2022 examining behavioral and pharmacological PTSD treatment effects on biobehavioral PTSD outcomes. RESULTS: Twenty-two studies met the inclusion criteria. Most studies evaluated behavioral treatment outcomes (n = 20), while only two studies evaluated pharmacological interventions. Five PTSD IPs were identified, including "impairments in working memory," "alterations in cognitive control," "unstable threat processing," "heightened fear or startle response," and "disturbances in sleep and wakefulness." This review offers preliminary support to suggest the utility of IP measures in assessing treatment efficacy; however, risk of bias and methodological limitations constrain the validity and generalizability of the results. CONCLUSIONS: The paucity of research combined with the heterogeneity of study methodologies and significant study limitations makes it difficult to draw strong conclusions regarding IP sensitivity to treatment. However, the existing body of research incorporating this framework shows potential for the IP approach to improve the translation of treatment efficacy from clinical trials to clinical settings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The effect of acute nicotine administration on human delay cued and context fear conditioning.

Nicotine has been shown to facilitate hippocampal-dependent context fear conditioning (FC), but not hippocampal-independent delay cued fear conditioning. Studies examining the effects of nicotine on learned fear have been exclusively limited to nonhumans. The present study aimed to translate nonhuman findings by investigating the effects of nicotine on cued and context fear in humans using a virtual reality (VR) analog of the fear conditioning task. Sixty-seven nicotine-using undergraduates were randomly assigned to receive either a 2 mg nicotine or placebo lozenge prior to conditioning. During conditioning, participants were confined to a virtual room and were conditioned to green floodlight presentations (conditioned stimulus [CS +]) paired with a wrist shock (unconditioned stimulus [US]). A red floodlight served as the CS- during which no shock occurred. Delay cued and context fear testing immediately followed conditioning. Physiological skin conductance responses (SCRs) were recorded continuously throughout all sessions. Nicotine enhanced context fear conditioning such that SCRs to the shock-paired context were significantly greater for the nicotine group than the placebo group. Nicotine did not enhance delay cued fear. Exploratory analyses examining the relationship between fear conditioning and self-reported anxiety revealed that relative to those with lower levels of trait anxiety, nicotine-treated individuals with higher trait anxiety levels were less likely to demonstrate differential conditioning to the shock-paired cue. These findings support abundant nonhuman literature indicating that nicotine facilitates hippocampus-dependent versions of fear conditioning in humans. Results also suggest a role for dysregulated safety learning in pathological anxiety, which may be exacerbated by nicotine use. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

PTSD symptom heterogeneity and alcohol-related outcomes in U.S. military veterans: Indirect associations with coping strategies.

INTRODUCTION: This study investigated the role of coping strategies in mediating the relationship between the 7-factor model of posttraumatic stress disorder (PTSD) symptoms and alcohol misuse in veterans. METHODS: Data were analyzed from 615 veterans from a nationally representative study of U.S. veterans who met criteria for probable full or subthreshold PTSD. Path analyses examined the role of self-sufficient, socially-supported, and avoidant coping strategies in mediating associations between PTSD symptom clusters and alcohol use disorder (AUD), alcohol consumption, and alcohol-related consequences. RESULTS: Negative affect PTSD symptoms were associated with AUD through increased use of avoidant coping. Additionally, dysphoric arousal PTSD symptoms were associated with AUD; avoidant coping was associated with AUD and increased alcohol consumption; self-sufficient coping was associated with reduced AUD likelihood anhedonia symptoms with decreased use of self-sufficient coping; and negative affect with decreased use of socially-supported coping and increased use of avoidant coping. CONCLUSIONS: Results underscore the importance of avoidant coping strategies as potential mediators of the relation between PTSD symptoms and AUD. Interventions designed to mitigate engagement in avoidant coping strategies, and to bolster engagement in self-sufficient and socially-supported strategies may help reduce alcohol misuse in veterans with full or subthreshold PTSD.

Disentangling the association between PTSD symptom heterogeneity and alcohol use disorder: Results from the 2019-2020 National Health and Resilience in Veterans Study.

Veterans are at increased risk of comorbid posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) relative to civilians. Few studies have explored the association between distinct PTSD symptoms and AUD in veterans, and existing findings are highly discrepant. This study aimed to address this gap and equivocal association by evaluating which PTSD symptom clusters are most associated with AUD in a veteran sample using the 7-factor 'hybrid' model of PTSD. Data were analyzed from the 2019-2020 National Health and Resilience in Veterans Study (NHRVS), a nationally representative survey of 4069 U.S. veterans. Veterans completed self-report measures to assess current PTSD symptoms and AUD. Multivariable logistic regression and relative importance analyses were conducted to examine associations between the 7-factor model of PTSD symptoms and AUD. Adjusting for sociodemographic, military, trauma factors, and depressive symptoms, scores on the dysphoric arousal (20.7% relative variance explained [RVE]) and externalizing behaviors (19.0% RVE) symptom clusters were most strongly associated with AUD in the full sample, while externalizing behaviors (47.7% RVE), anxious arousal (23.9% RVE), and dysphoric arousal (12.4%) accounted for the majority of explained variance in veterans who screened positive for PTSD. Results of this nationally representative study of U.S. veterans highlight the importance of externalizing behaviors and arousal symptoms of PTSD as potential drivers of AUD in this population. The 7-factor hybrid model of PTSD provides a more nuanced understanding of PTSD-AUD associations, and may help inform risk assessment and more personalized treatment approaches for veterans with and at-risk for AUD.

Nicotine Facilitation of Conditioned Place Preference to Food Reward in Humans.

BACKGROUND: Nicotine has recently been shown to enhance the motivational value of non-nicotine stimuli in nonhumans. To investigate whether nicotine also enhances reward in humans, we used a virtual translation of the conditioned place preference (CPP) paradigm to examine nicotine's reward-enhancing effects using a low-dose 2 mg nicotine lozenge targeted to a mild use population. Methods: Sixty-eight nicotine-using undergraduates were randomly assigned to receive either a 2 mg nicotine or placebo lozenge prior to conditioning. During each of six, three-minute conditioning sessions, participants were confined to one of two VR rooms. In one room, they received real chocolate M&Ms, whereas no M&Ms were administered in the other room. Following conditioning, a three-minute free-access test session occurred during which participants had unrestricted access to both rooms without reward. Results: Individuals who received nicotine demonstrated a CPP by spending significantly more time in the room previously paired with M&Ms compared to the unrewarded room (p = 0.04). Those who received placebo did not demonstrate a CPP (p > 0.05). Moreover, we observed no significant differences between treatment groups in terms of the amount of time spent in each virtual room. Conclusion: While nicotine seems to facilitate CPP expression for a virtual environment previously paired with chocolate food rewards, further characterization of the mechanism by which this occurs is needed.

The effects of nicotine on conditioning, extinction, and reinstatement in humans.

Nicotine has been shown to enhance the reinforcement and reward-responsiveness of non-nicotine stimuli. To determine whether nicotine enhances the strength of conditioning to context, undergraduate participants with varying levels of nicotine dependence were recruited for a two-day study and tested on a virtual reality (VR) conditioned place preference (CPP) paradigm. On day one, participants explored two virtual rooms where they received multiple pairings of M&M rewards in one room and no rewards in the other room, followed by a free-access test session with no rewards. On day two, participants received three test sessions to assess extinction. Subsequently, participants received M&Ms. in a novel context and were then tested for reinstatement. Prior to testing on each day, subjects were administered either nicotine (4mg) or placebo lozenges, in a between-subjects, four-group, 2×2 design (nicotine or placebo on days 1 and 2). After conditioning on day one, only participants who received placebo exhibited a CPP by spending significantly more time in the room previously-paired with M&Ms. Contrary to our hypothesis, nicotine-treated participants did not display a significant CPP, and there were no significant differences between treatment groups. However, post hoc analysis indicated that in a subset of participants with greater nicotine dependence, the nicotine group displayed a CPP by rating the M&M-paired room as significantly more enjoyable than those who received placebo. Additionally, while neither treatment group showed significant place preferences during the first two extinction sessions on Day 2, individuals who received nicotine on Day 1 or placebo on Day 2 spent significantly more time in the M&M-paired room during the final extinction session. Finally, those who received nicotine on Day 2 exhibited significantly greater reinstatement compared to placebo-treated participants. These results partially support preclinical evidence that nicotine can affect learning, extinction, and reinstatement.

Conditioned place preferences in humans using secondary reinforcers.

The goal of this experiment was to examine whether a conditioned place preference could be established in humans using a secondary reinforcer that provided little obvious reward to the participants. Two experiments were conducted to answer this question. In Experiment 1, 244 undergraduates were placed into a VR environment consisting of two visually distinct rooms connected by a door. Throughout the experiment, one room was randomly paired with occasional point rewards while the other unique room was never paired with rewards. Participants received thee pairings in each room. After a short break, a test session was administered, and participants were given free access to the entire VR environment and no point rewards were administered. On the test day, we observe that participants displayed a significant CPP for the room paired with points, as evidenced by significant differences in rating each of the rooms in terms of enjoyment. In Experiment 2, 77 undergraduates were tested using a biased conditioning approach in which an initial test session was conducted to obtain the participant's preferred room bias, and then the least-preferred room was designated as the points reward room for each participant. Using this biased conditioning approach, participants spent a significantly greater amount of time in the points-paired room. In this case, participants showed preferences based on explicit and implicit measures. These results suggest new approaches to examine the role of secondary reinforcers in nontraditional addictions such as internet, gaming, and gambling dependencies.

Pavlovian conditioning to food reward as a function of eating disorder risk.

The aim of this experiment was to examine the extent to which eating disorder risk affects the strength of food-reward conditioning. Eighty food-restricted undergraduates were placed into a VR environment consisting of two visually distinct rooms. Participants underwent multiple pairing sessions in which they were confined into one of the two rooms and explored a VR environment. Room A was paired with real-life M&Ms for three sessions, and Room B was paired with no food for three sessions. After a short delay, a test session was administered, and participants were given free access to the entire VR environment for 5 min. Participants also completed the Eating Attitudes Test (EAT-26; [11]), which is a standard screening tool of eating disorder risk. Participants displayed a significant conditioned place preference for the VR room previously paired with food, and they displayed a significant explicit preference for the M&M-paired room in a forced-choice test. There was a significant positive correlation between place preference strength and scores on the dieting subscale of the EAT-26. Additionally, ratings of the no-food room were significantly lower as dieting scores increased. This suggests that components of eating disorder risk can influence basic conditioning strength to places associated with food reward. For both males and females, additional correlations between eating disorder risk subscales and conditioning variables are discussed, and implications for future research are proposed in hopes of understanding how conditioning paradigms can provide insight into treating and preventing eating disorders.