Ursula S. Myers

Reward circuit function in high BMI individuals with compulsive overeating: Similarities with addiction

CONTEXT The rising rate of overweight and obese individuals among developing countries despite focused efforts on prevention and treatment underscores not only the need to better define the physiological factors that contribute to weight problems, but also the need to elucidate the neurobiological mechanisms of the self-regulatory failure over eating that leads to weight problems. Emergent findings suggest an overlapping model of addiction and compulsive overeating. OBJECTIVE Our goal was to examine whether neural hyper-responsivity to reward typically associated with substance abuse could also be seen in individuals exhibiting binge-eating behavior. DESIGN Participants completed self-assessments of demographic information and eating behavior. Neurofunctional data were collected via functional MRI (fMRI) scans while participants were exposed to personally relevant high-calorie cues. SETTING The participants were recruited from the general community. PARTICIPANTS Twenty-six individuals with high body mass index (BMI)>25 and moderate binge-eating behavior as assessed by the Binge Eating Scale (BES) were recruited for this study. MAIN OUTCOME MEASURES fMRI BOLD response during exposure to high-calorie taste cues. RESULTS The results showed that exposure to high-calorie taste cues elicited fMRI BOLD response in the reward system of individuals with high BMI, and, more importantly, that this hyper-responsivity increases with greater number of binge-eating symptoms (cluster-corrected p<.05, z=1.9). CONCLUSIONS These findings support an overlapping neural model of addiction and self-regulatory failure over eating that may lead to problems with weight in humans. These findings offer insight into the prevention and treatment of disordered eating.

Neural Effects of Positive and Negative Incentives during Marijuana Withdrawal

In spite of evidence suggesting two possible mechanisms related to drug-seeking behavior, namely reward-seeking and harm avoidance, much of the addiction literature has focused largely on positive incentivization mechanisms associated with addiction. In this study, we examined the contributing neural mechanisms of avoidance of an aversive state to drug-seeking behavior during marijuana withdrawal. To that end, marijuana users were scanned while performing the monetary incentive delay task in order to assess positive and negative incentive processes. The results showed a group x incentive interaction, such that marijuana users had greater response in areas that underlie reward processes during positive incentives while controls showed greater response in the same areas, but to negative incentives. Furthermore, a negative correlation between withdrawal symptoms and response in the amygdala during negative incentives was found in the marijuana users. These findings suggest that although marijuana users have greater reward sensitivity and less harm avoidance than controls, that attenuated amygdala response, an area that underlies fear and avoidance, was present in marijuana users with greater marijuana withdrawal symptoms. This is concordant with models of drug addiction that involve multiple sources of reinforcement in substance use disorders, and suggests the importance of strategies that focus on respective mechanisms.

Obstructive Sleep Apnea and Posttraumatic Stress Disorder among OEF/OIF/OND Veterans

OBJECTIVES This study examined: (a) the relationship between self-reported posttraumatic stress disorder (PTSD) symptoms and risk of obstructive sleep apnea (OSA) in a younger, Iraq and Afghanistan (OEF/OIF/OND) veteran sample seeking treatment for PTSD; and (b) the relationships between PTSD symptom scores and each risk factor of OSA (snoring, fatigue, high blood pressure/BMI). METHODS Participants were 195 Iraq and Afghanistan veterans presenting to a VA outpatient PTSD clinic for evaluation. Veterans were 21 to 59 years old (mean 33.40, SD 8.35) and 93.3% male (n = 182). Logistic regressions were run to examine whether veterans with greater PTSD symptom severity had an increased probability of screening as high risk for OSA, even after controlling for known risk factors (older age, positive smoking status, and use of CNS depressants). RESULTS Of 159 veterans screened, 69.2% were assessed as being at high risk for OSA. PTSD symptom severity increased the risk of screening positive for OSA. PTSD symptom severity increased risk of screening positive for snoring and fatigue, but not high blood pressure/BMI. CONCLUSIONS OEF/OIF/OND veterans with PTSD screen as high risk for OSA at much higher rates than those seen in community studies and may not show all classic predictors of OSA (i.e., older and higher BMI). This study is the first to suggest that the Berlin may be a useful screener for OSA in a younger OEF/OIF/OND veteran population with PTSD. Screening of younger veterans with PTSD for OSA should be standard care, and polysomnography and OSA interventions should be readily available to younger veterans.

Trauma-related guilt: conceptual development and relationship with posttraumatic stress and depressive symptoms.

Despite high prevalence and concerning associated problems, little effort has been made to conceptualize the construct of posttraumatic guilt. This investigation examined the theoretical model of trauma-related guilt proposed by Kubany and Watson (2003). This model hypothesizes that emotional and physical distress related to trauma memories partially mediates the relationship between guilt cognitions and posttraumatic guilt. Using path analysis, this investigation (a) empirically evaluated relationships hypothesized in Kubany and Watsons model, and (b) extended this conceptualization by evaluating models whereby guilt cognitions, distress, and posttraumatic guilt were related to posttraumatic stress disorder (PTSD) symptoms depression symptom severity. Participants were male U.S. Iraq and Afghanistan veterans (N = 149). Results yielded a significant indirect effect from guilt cognitions to posttraumatic guilt via distress, providing support for Kubany and Watsons model (β = .14). Findings suggested distress may be the strongest correlate of PTSD symptoms (β = .47) and depression symptoms (β = .40), and that guilt cognitions may serve to intensify the relationship between distress and posttraumatic psychopathology. Research is needed to evaluate whether distress specific to guilt cognitions operates differentially on posttraumatic guilt when compared to distress more broadly related to trauma memories.

Treatment Engagement: Female Survivors of Intimate Partner Violence in Treatment for PTSD and Alcohol Use Disorder

Objective: Treatment engagement rates are low for individuals with comorbid posttraumatic stress disorder (PTSD) and alcohol use disorders across available interventions and treatment modalities. A better understanding of who does and does not engage in treatment can help improve retention, completion, and subsequent treatment outcomes. Methods: Forty female survivors of intimate partner violence with PTSD and alcohol use disorder participated in a randomized controlled trial comparing twenty-five 90-minute sessions of either modified Seeking Safety or Facilitated Twelve-Step in a community-based outpatient clinic. This study examined differences in demographics and pre-treatment PTSD symptoms and alcohol use between participants who engaged in treatment (attended ≥ 6 sessions, n = 18) and those who dropped out (n = 22). Results: There were no significant differences in PTSD or alcohol use disorder symptoms between treatment conditions. Women who engaged in therapy versus those who did not were significantly older (M = 46.2, SD = 9.14 vs. M = 38.95, SD = 10.49, respectively; p =.027), and had fewer dependents (M =.17, SD =.38, range = 0–1 vs. M =.95, SD = 1.66, range = 1–7, respectively; p =.046). Greater avoidance/numbing PTSD symptoms (OR = 1.13, p =.028, 95% CI [1.02–1.25]) and more years of heavy drinking (OR = 1.04, p =.03, 95% CI [1.00–1.07]) were also significantly associated with treatment engagement. Conclusions: This study replicates previous findings suggesting a need for additional retention strategies for younger women with dependents in comorbid PTSD and alcohol use disorder treatment. This is an analysis of data collected as part of a clinical trial registered as NCT00607412, at www.clinicaltrials.gov.

The Role of Alcohol Expectancies in Drinking Behavior among Women with Alcohol Use Disorder and Comorbid Posttraumatic Stress Disorder

Abstract Understanding how alcohol expectancies relate to alcohol use among individuals with concurrent alcohol use disorder (AUD) and Posttraumatic Stress Disorder (PTSD) is important to understanding and treating this comorbidity. This study examined the role of positive and negative alcohol expectancies and PTSD symptoms in drinking behavior in a comorbid female sample. Participants were women (n = 33; 56% Caucasian) seeking AUD and PTSD treatment in an outpatient community co-occurring disorders program. Hypotheses related to drinking days and alcohol problems outcomes were evaluated using negative binomial hierarchical regression. PTSD symptoms were associated with fewer reported days of alcohol-related problems. Negative expectancies related to negative changes in social behavior associated with drinking days and cognitive and motor impairment associated with problems. Both the general positive expectancies score and specific global positive change subscale were uniquely associated with drinking and alcohol-related problems days after controlling for PTSD symptom severity and negative expectancies scores. Results suggest that both negative and positive expectancies about alcohol’s effects are important correlates of drinking behavior among women with AUD and PTSD, with positive expectancies playing a potentially more salient role on use and consequences than symptom severity and negative expectancies.

Evidence-based psychotherapy completion and symptom improvement among returning combat veterans with PTSD.

Objective: Despite the availability of evidence-based psychotherapy (EBP) for posttraumatic stress disorder (PTSD) in the Veterans Health Administration, treatment completion rates are low and not all veterans benefit from these treatments. Understanding factors associated with PTSD EBP completion and symptom improvement is critical to improving completion rates and effectiveness. Method: This chart review study used the Andersen Behavioral Model to examine whether predisposing characteristics (nonmodifiable characteristics such as demographics), enabling factors (modifiable logistic variables that can facilitate or impede treatment use), and need factors (clinical characteristics such as symptom severity or comorbidities) predicted treatment completion or symptom improvement following PTSD EBP treatment among 82 Iraq and Afghanistan combat veterans. Logistic regression was used to examine treatment completion, and repeated measures analysis of variance was used to examine changes in PTSD and depression symptoms following treatment. Results: EBP completers had greater improvement in PTSD symptoms than did EBP dropouts. Need factors (lack of comorbid substance use disorders and having problems with family members/significant others) were related to treatment completion, whereas enabling resources (receiving individual rather than group treatment) were related to symptom improvement. Conclusions: This is one the first studies to use a comprehensive model to examine factors relevant to treatment completion and symptom improvement. Results suggest that nonmodifiable predisposing characteristics do not drive treatment completion and symptom improvement, underscoring the potential importance of targeting enabling resources and needs factors for intervention.