Kristin Gregor

The shared neuroanatomy and neurobiology of comorbid chronic pain and PTSD: therapeutic implications.

Chronic pain and posttraumatic stress disorder (PTSD) are disabling conditions that affect biological, psychological, and social domains of functioning. Clinical research demonstrates that patients who are affected by chronic pain and PTSD in combination experience greater pain, affective distress, and disability than patients with either condition alone. Additional research is needed to delineate the interrelated pathophysiology of chronic pain and PTSD, with the goal of facilitating more effective therapies to treat both conditions more effectively; current treatment strategies for chronic pain associated with PTSD have limited efficacy and place a heavy burden on patients, who must visit various specialists to manage these conditions separately. This article focuses on neurobiological factors that may contribute to the coprevalence and synergistic interactions of chronic pain and PTSD. First, we outline how circuits that mediate emotional distress and physiological threat, including pain, converge. Secondly, we discuss specific neurobiological mediators and modulators of these circuits that may contribute to chronic pain and PTSD symptoms. For example, neuropeptide Y, and the neuroactive steroids allopregnanolone and pregnanolone (together termed ALLO) have antistress and antinociceptive properties. Reduced levels of neuropeptide Y and ALLO have been implicated in the pathophysiology of both chronic pain and PTSD. The potential contribution of opioid and cannabinoid system factors also will be discussed. Finally, we address potential novel methods to restore the normal function of these systems. Such novel perspectives regarding disease and disease management are vital to the pursuit of relief for the many individuals who struggle with these disabling conditions.

The relationship between reward-based learning and nicotine dependence in smokers with schizophrenia.

Cigarette smoking rates remain remarkably high in schizophrenia relative to smoking in other psychiatric groups. Impairments in the reward system may be related to elevated rates of nicotine dependence and lower cessation rates in this psychiatric group. Smokers with schizophrenia and schizoaffective disorder (SWS; n=15; M(age)=54.87, S.D.=6.51, 100% male) and a non-psychiatric control group of smokers (NCL; n=16; M(age)=50.38, S.D.=11.52; 93.8% male) were administered a computerized signal detection task to measure reward-based learning. Performance on the signal detection task was assessed by response bias, discriminability, reaction time, and hit rate. Clinician-assessed and self-reported measures of smoking and psychiatric symptoms were completed. SWS exhibited similar patterns of reward-based learning compared to control smokers. However, decreased reward-based learning was associated with increased levels of nicotine dependence in SWS, but not among control smokers. Nicotine withdrawal and urge to smoke were correlated with anhedonia within the SWS group. Among SWS, reduced reward responsiveness and increased anhedonia were associated with and may contribute to greater co-occurring nicotine dependence. These findings emphasize the importance of targeting reward system functioning in smoking cessation treatment for individuals with schizophrenia.

Psychophysiologic reactivity, subjective distress, and their associations with PTSD diagnosis.

Intense subjective distress and physiologic reactivity upon exposure to reminders of the traumatic event are each diagnostic features of posttraumatic stress disorder (PTSD). However, subjective reports and psychophysiological data often suggest different conclusions. For the present study, we combined data from five previous studies to assess the contributions of these two types of measures in predicting PTSD diagnosis. One hundred fifty trauma-exposed participants who were classified into PTSD or non-PTSD groups based on structured diagnostic interviews completed the same script-driven imagery procedure, which quantified measures of psychophysiologic reactivity and self-reported emotional responses. We derived four discriminant functions (DiscFxs) that each maximally separated the PTSD from the non-PTSD group using (1) psychophysiologic measures recorded during personal mental imagery of the traumatic event; (2) self-report ratings in response to the trauma imagery; (3) psychophysiologic measures recorded during personal mental imagery of another highly stressful experience unrelated to the index traumatic event; and (4) self-report ratings in response to this other stressor. When PTSD status was simultaneously regressed on all four DiscFxs, trauma-related psychophysiological reactivity was a significant predictor, but physiological reactivity resulting from the highly stressful, but not traumatic script, was not. Self-reported distress to the traumatic experience and the other stressful event were both predictive of PTSD diagnosis. Trauma-related psychophysiologic reactivity was the best predictor of PTSD diagnosis, but self-reported distress contributed additional variance. These results are discussed in relation to the Research Domain Criteria framework.

Does Guilt Mediate the Association Between Tonic Immobility and Posttraumatic Stress Disorder Symptoms in Female Trauma Survivors

Tonic immobility (TI) is an involuntary freezing response that can occur during a traumatic event. TI has been identified as a risk factor for posttraumatic stress disorder (PTSD), although the mechanism for this relationship remains unclear. This study evaluated a particular possible mechanism for the relationship between TI and PTSD symptoms: posttraumatic guilt. To examine this possibility, we assessed 63 female trauma survivors for TI, posttraumatic guilt, and PTSD symptom severity. As expected, the role of guilt in the association between TI and PTSD symptom severity was consistent with mediation (B = 0.35; p < .05). Thus, guilt may be an important mechanism by which trauma survivors who experience TI later develop PTSD symptoms. We discuss the clinical implications, including the importance of educating those who experienced TI during their trauma about the involuntary nature of this experience.

Differences in smoking behavior and attitudes among Puerto Rican, Dominican, and non-Latino white caregivers of children with asthma

Purpose. No studies have examined the differences in smoking attitudes and behavior between Dominicans (DRs) and Puerto Ricans (PRs). Identification of pretreatment differences is important for cultural adaptation of evidenced-based smoking cessation treatments. Design. Secondary analysis. Setting/Intervention. Three home visits for asthma education and smoking cessation. Subjects. Caregivers who smoke and have a child with asthma: DRs (n = 30), PRs (n = 67), and non-Latino whites (n = 128; NLWs). Measures. Baseline assessment of psychosocial variables. Analyses. Controlled for age, education, and acculturation. Results. Compared with DRs, PRs were more acculturated, more nicotine dependent, less motivated and confident to quit, and identified more pros of smoking (all p < .05). Compared with NLWs, PRs were less likely to be employed, smoked fewer cigarettes per day, and had lower education, greater depressed mood, greater pros and cons of smoking, less social support, and higher child asthma morbidity (all p < .05). Compared with NLWs, DRs were less nicotine dependent, more confident to quit, and less likely to live with a smoker; reported greater cons of smoking and greater stress; and were more likely to have a household smoking ban (DRs 60% vs. NLWs 33.6%). Only 3.3% of DRs were precontemplators vs. 16.4% (PRs) and 10.9% (NLWs). Conclusions. PRs appear to have more factors associated with risk of smoking treatment failure; DRs appear to have more protective factors. Examination of the role of these smoking attitudes as potential moderators and mediators of smoking behavior are needed to guide the cultural adaptation of evidenced-based treatments. (Am J Health Promot 2011;25[5 Supplement]:S91—S95.)

Deployment stress, tobacco use, and postdeployment posttraumatic stress disorder: Gender differences.

OBJECTIVE Epidemiological research has demonstrated that tobacco use and posttraumatic stress disorder (PTSD) frequently co-occur and are highly prevalent among Veterans; research with female Veterans is limited. Given the increasing numbers of women deployed to combat zones in recent conflicts, the objective of the current study was to examine gender-specific associations between deployment stress, tobacco use and postdeployment PTSD symptoms. METHOD Two thousand thirteen Veterans deployed to Afghanistan and Iraq (50.9% female; mean age = 35.53) completed a postdeployment, mailed survey that assessed tobacco use before, during, and after deployment, deployment stressors, and postdeployment PTSD symptoms. RESULTS Warfare stress was associated with initiation and increases in tobacco use during deployment in both men and women, whereas harassment stress was associated with initiation and increases in tobacco use in women only. Only among women was continued postdeployment tobacco use associated with postdeployment PTSD symptoms. CONCLUSIONS We found a dose-dependent relationship between deployment stress and adoption and escalation of tobacco use; the stressors that provoked initiation and escalation of tobacco use differed by gender. Continued tobacco use after deployment was associated with PTSD in women suggesting that women used tobacco more selectively than men to regulate negative affect. Implications of this work are that training before combat and during combat on healthy means of coping with deployment stress is needed to prevent tobacco use. For women, reducing harassment stress during deployment and early treatment of acute stress and PTSD during and soon after deployment may prevent intractable tobacco use.

Sweat pore reactivity as a surrogate measure of sympathetic nervous system activity in trauma-exposed individuals with and without posttraumatic stress disorder

Stress analysis by FLIR (forward-looking infrared) evaluation (SAFE) has been demonstrated to monitor sweat pore activation (SPA) as a novel surrogate measure of sympathetic nervous system (SNS) activity in a normal population. SNS responses to a series of 15 1-s, 82 dB, white noise bursts were measured by skin conductance (SC) and SAFE monitoring of SPA on the fingers (FiP) and face (FaP) in 10 participants with posttraumatic stress disorder (PTSD) and 16 trauma-exposed participants without PTSD (Mage  = 48.92 ± 12.00 years; 26.9% female). Within participants, SC and FiP responses across trials were strongly correlated (r = .92, p < .001). Correlations between SC and FaP (r = .76, p = .001) and between FiP and FaP (r = .47, p = .005) were smaller. The habituation of SNS responses across the 15 trials was substantial (SC: d = -2.97; FiP: d = -2.34; FaP: d = -1.02). There was a strong correlation between habituation effects for SC and FiP (r = .76, p < .001), but not for SC and FaP (r = .15, p = .45) or FiP and FaP (r = .29, p = .16). Participants with PTSD showed larger SNS responses to the first loud noise than those without PTSD. PTSD reexperiencing symptoms assessed by the PTSD Checklist on the day of testing were associated with the SNS responses to the first loud noise measured by SC (d = 1.19) and FiP (d = .99), but not FaP (d = .10). This study confirms convergence of SAFE and SC as valid measures of SNS activity. SAFE FiP and SC responses were highly predictive of self-rated PTSD reexperiencing symptoms. SAFE may offer an attractive alternative for applications in PTSD and similar populations.

Utilizing reliable and clinically significant change criteria to assess for the development of depression during smoking cessation treatment: the importance of tracking idiographic change.

Studies typically measure mood changes during smoking cessation treatment in two ways: (a) by tracking mean change in depression scores or (b) by tracking the incidence of major depression development using diagnostic assessments. However, tracking mean change does not capture variability in individual mood trajectories, and diagnosing participants at multiple time points is time and labor intensive. The current study proposes a method of assessing meaningful increases in depression without the use of diagnostic assessments by utilizing reliable and clinically significant change criteria. This method was applied to 212 participants in a smoking cessation trial to explore the relationship between smoking status and depressed mood, assessed at baseline, end-of-treatment, and 2-, 6-, and 12-month follow-ups. High rates of reliable (24-28%) and both reliable and clinically significant increases (23-24%) in depressed mood were observed across all participants, regardless of whether or not they achieved abstinence. However, when we calculated group mean change in depression during the trial, only decreases in depressed mood where observed across several intervals. Findings indicate that utilizing reliable and clinically significant change criteria to track symptoms of depression during smoking cessation treatment leads to different conclusions than simply tracking mean changes. We propose that a combination of reliable and clinically significant change criteria may serve as a useful proxy measure for the development of major depressive disorder during smoking cessation.