Canine companionship is associated with modification of attentional bias in posttraumatic stress disorder

Bedtime regularity predicts positive affect among veterans with posttraumatic stress disorder: an ecological momentary assessment study

BACKGROUND

Regularizing bedtime and out-of-bed times is a core component of behavioral treatments for sleep disturbances common among patients with posttraumatic stress disorder (PTSD). Although improvements in subjective sleep complaints often accompany improvements in PTSD symptoms, the underlying mechanism for this relationship remains unclear. Given that night-to-night sleep variability is a predictor of physical and mental well-being, the present study sought to evaluate the effects of bedtime and out-of-bed time variability on daytime affect and explore the optimal window lengths of over which variability is calculated.

METHODS

For about 30 days, male U.S. military veterans with PTSD (N = 64) in a residential treatment program provided ecological momentary assessment data on their affect and slept on beds equipped with mattress actigraphy. We computed bedtime and out-of-bed time variability indices with varying windows of days. We then constructed multilevel models to account for the nested structure of our data and evaluate the impact of bedtime and out-of-bed time variability on daytime affect.

RESULTS

More regular bedtime across 6-9 days was associated with greater subsequent positive affect. No similar effects were observed between out-of-bed time variability and affect.

CONCLUSIONS

Multiple facets of sleep have been shown to differently predict daily affect, and bedtime regularity might represent one of such indices associated with positive, but not negative, affect. A better understanding of such differential effects of facets of sleep on affect will help further elucidate the complex and intertwined relationship between sleep and psychopathology.

TRIAL REGISTRATION

The trial retrospectively was registered on the Defense Technical Information Center website: Award # W81XWH-15-2-0005.

Heart Rate During Sleep in PTSD Patients: Moderation by Contact with a Service Dog

There is growing interest in the potential health benefits of dog ownership in both the lay and scientific communities. Large reductions in risk for cardiovascular disease and all-cause mortality in dog owners relative to non-owners have been observed in epidemiological samples. Persons diagnosed with posttraumatic stress disorder exhibit elevated risk for cardiovascular disease. The current study tested a sample of 45 U.S. military veterans with deployment-related posttraumatic stress disorder employing an intensive, longitudinal, within-subjects design contrasting sleep heart rate on nights with and without a service dog. As participants were engaged in residential psychiatric treatment, sleep opportunities, waking activities, meals, and medications, were consistently scheduled. The primary recording methodology, mattress actigraphy, enabled passive quantification of heart rate over a total sample of 1097 nights. Service dog contact was associated with reduced sleep heart rate especially in participants with more severe PTSD. Longer-term longitudinal studies will be needed to assess the durability and asymptotic magnitude of this effect. An unexpected effect of nights in study was associated with increased heart rate consistent with hospitalization-associated deconditioning.

Longitudinal profiles of sleep during residential PTSD treatment

We investigated longitudinal profiles of objectively measured sleep periods (SP) over the course of residential treatment for posttraumatic stress disorder (PTSD) in a cohort of U.S. male veterans. Participants (N = 190) slept on mattress-actigraphy systems in a Veterans Affairs (VA) residential PTSD program. The final sample included 4078 sleep periods. Latent class mixed model analyses were used to identify between-subject profiles in sleep period durations, controlling for daily medication intake, over the first fifty days of residency. Logistic regression was used to determine the association of pre-treatment characteristics with identified profiles. Three longitudinal profiles of sleep period characterized most of the sample: 'stable' (56%), 'decreasing' (35%), and 'increasing' (8%). Less severe pre-treatment PTSD avoidance symptoms predicted membership in the 'decreasing' class and increased depression symptoms were predictive of membership in the 'increasing' class. Nearly half of the sample reported a summary change of 1 h or more over the course of the initial 50-nights in the program. Future work is needed to identify how these profiles might drive inpatient treatment decisions regarding the provision of adjunctive sleep-focused treatment such as cognitive-behavioral treatment for insomnia or hypnotic medications.

Male and female impairments in odor span are observed in a rat model of PTSD

Posttraumatic stress disorder (PTSD) is associated with neural and behavioral alterations in response to trauma exposure, including working memory impairments. Rodent models of PTSD have not fully investigated chronic or reactive working memory deficits, despite clinical relevance. The present study uses footshock to induce a posttraumatic stress state in male and female rats and evaluates the effect of footshock and trauma-paired odor cues on working memory performance in the odor span task. Results demonstrate the emergence of chronic deficits in working memory among animals exposed to footshock by 3 wk after traumatic stress. The presentation of a trauma-paired odor cue was associated with further decrement in working memory performance for male animals. Furthermore, anxiety-like behaviors associated with the PTSD-like phenotype could predict the degree of working memory impairment in response to the trauma-paired odor cue. This study enhances validation of an existing rodent model of PTSD through replication of the clinical observations of working memory deficits associated with PTSD and provides novel insight into effects in female rodents. This will facilitate work to probe underlying mechanistic dysregulation of working memory following footshock trauma exposure and future development of novel treatment strategies.

Reading the mind in the eyes in PTSD: Limited Moderation by the presence of a service dog

Persons with posttraumatic stress disorder (PTSD) frequently experience relationship failures in family and occupational domains resulting in loss of social supports. Prior research has implicated impairments in social cognition. The Reading the Mind in the Eyes Test (RMET) measures a key component of social cognition, the ability to infer the internal states of other persons based on features of the eyes region of the face; however, studies administering this popular test to persons with PTSD have yielded mixed results. This study assessed RMET performance in 47 male U.S. military Veterans with chronic, severe PTSD. Employing a within-subjects design that avoided selection biases, it aimed specifically to determine whether components of RMET performance, including accuracy, response latency, and stimulus dwell time, were improved by the company of a service dog, an intervention that has improved social function in other populations. RMET accuracies and response latencies in this PTSD sample were in the normal range. The presence of a familiar service dog did not improve RMET accuracy, reduce response latencies, or increase dwell times. Dog presence increased the speed of visual scanning perhaps consistent with reduced social fear.

The Effect of a PTSD Service Dog on Military Veterans' Medication Regimens: A Cross-Sectional Pilot Study

Recent research suggests that service dogs may have clinically-relevant benefits for military veterans with posttraumatic stress disorder (PTSD). However, the effects of PTSD service dogs on veterans' medication use has been largely unexplored. The objective of this study was to quantify the effect of PTSD service dogs on medication use among a population of military veterans with PTSD. In a cross-sectional design, United States post-9/11 military veterans with PTSD were recruited from a single service dog provider including veterans living with a PTSD service dog (n = 52) and veterans on the waitlist (n = 44). Both populations of veterans received treatment as usual. Participants completed an online survey of self-reported medication regimens and medication changes. Regression models quantified the effect of having a service dog on physical health, mental health, pain, and sleep medications while controlling for confounding variables (age, sex, relationship status, traumatic brain injuries, and physical health). Results indicated that there were no significant effects of having a service dog on overall self-reported medication use nor any specific medication category (p's > 0.06). However, veterans with a service dog were more likely than those on the waitlist to report that their doctor had decreased dosage or removed medications since getting their service dog. The results of this preliminary cross-sectional research should be interpreted with caution, as future within-subject and pharmacy-verified research is necessary to understand the causality of these findings.

Effectiveness of animal-assisted interventions for children and adults with post-traumatic stress disorder symptoms: a systematic review and meta-analysis

Background: Animal-assisted interventions (AAI) are increasingly applied for people with post-traumatic stress disorder (PTSD) symptoms albeit its effectiveness is unclear.Objectives: To examine the effectiveness of AAI for treating PTSD symptoms.Method: We searched 11 major electronic databases for studies reporting quantitative data on effects of AAI for children and adults with PTSD symptoms. Of 22'211 records identified, we included 41 studies with 1111 participants in the systematic review comprising eight controlled studies with 469 participants in the meta-analysis. We conducted random-effects meta-analyses with all controlled studies based on standardized mean differences (SMD), and calculated standardized mean change (SMC) as effect sizes for studies with a pre-post one-group design. Two independent researchers assessed the quality of the included studies using the NIH Study Quality Assessment Tools. The primary outcome was PTSD or depression symptom severity measured via a standardized measurement at pre- and post-intervention assessments.Results: There was a small but not statistically significant superiority of AAI over standard PTSD psychotherapy (SMD = -0.26, 95% CI: -0.56 to 0.04) in reducing PTSD symptom severity while AAI was superior to waitlist (SMD = -0.82, 95% CI: -1.56 to 0.08). Getting a service dog was superior to waiting for a service dog (SMD = -0.58, 95% CI: -0.88 to -0.28). AAI led to comparable effects in reducing depression as standard PTSD psychotherapy (SMD = -0.03, CI: -0.88 to 0.83). Pre-post comparisons showed large variation for the reduction in PTSD symptom severity, with SMCs ranging from -0.38 to -1.64, and for depression symptom severity, ranging from 0.01 to -2.76. Getting a service dog lowered PTSD symptoms between -0.43 and -1.10 and depression with medium effect size of -0.74.Conclusions: The results indicate that AAI are efficacious in reducing PTSD symptomatology and depression. Future studies with robust study designs and large samples are needed for valid conclusions.

Social cognition in post-traumatic stress disorder: A systematic review

OBJECTIVES

Post-traumatic stress disorder (PTSD) is a common psychiatric condition. Patients with PTSD have marked symptoms that significantly impair their social and emotional abilities, and numerous studies have explored this issue. We hypothesized that impairment of social cognition takes part in functional disability of individuals with PTSD.

METHODS

We conducted a systematic review by querying PubMed database for the titles of articles published up to February 2018 with the terms [PTSD] [Post traumatic disorder] AND [Emotion recognition] OR [Facial expression of emotion] OR [Facial expression perception] OR [Empathy] OR [Affective empathy] OR [Mentalizing] OR [Social cognition] OR [Theory of Mind] OR [Mental state attribution] OR [Cognitive empathy] OR [Emotional empathy] OR [Social behaviour deficits].

RESULTS

Our results suggest that affective and cognitive aspect of theory of mind is comprehensively disturbed in patients with PTSD, showing a significant impairment in their ability to predict what others feel, think, or believe. They could also be massively altered in their perception of basic emotional expressions whether it is an expression of threat or happiness. Their affective empathy appears to be systematically disturbed and correlated to verbal and/or physical aggressive behaviour.

CONCLUSIONS

Social cognition is disturbed in PTSD and should be regarded as an important symptom. Damages in social cognition seem to take part in the functional disability of people with PTSD. We highlight the interest of a systematic assessment of social cognition in the care of patients with PTSD and suggest which tests could be the most relevant for this evaluation.

PRACTITIONER POINTS

•PTSD is no longer regarded as a subtype of anxiety disorder, but as part of a new category in the DSM-5. In clinical practice, symptoms tied to alterations in arousal and reactivity - such as irritability and vigilance - and to the disturbance of cognition and mood, are particularly closely correlated with poorer quality of life. Impaired social cognition clearly impacts the functional disability of people with PTSD. There are potential benefits of individualized cognitive remediation based on empathy and the emotional component of ToM (cognitive remediation, cognitive-behavioural therapy, therapeutic education, etc.) in PTSD people.

Angry and Fearful Face Conflict Effects in Post-traumatic Stress Disorder

In the presence of threatening stimuli, post-traumatic stress disorder (PTSD) can manifest as hypervigilance for threat and disrupted attentional control. PTSD patients have shown exaggerated interference effects on tasks using trauma-related or threat stimuli. In studies of PTSD, faces with negative expressions are often used as threat stimuli, yet angry and fearful facial expressions may elicit different responses. The modified Eriksen flanker task, or the emotional face flanker, has been used to examine response interference. We compared 23 PTSD patients and 23 military controls on an emotional face flanker task using angry, fearful and neutral expressions. Participants identified the emotion of a central target face flanked by faces with either congruent or incongruent emotions. As expected, both groups showed slower reaction times (RTs) and decreased accuracy on emotional target faces, relative to neutral. Unexpectedly, both groups showed nearly identical interference effects on fearful and neutral target trials. However, post hoc testing suggested that PTSD patients showed faster RTs than controls on congruent angry faces (target and flanker faces both angry) relative to incongruent, although this finding should be interpreted with caution. This possible RT facilitation effect with angry, but not fearful faces, also correlated positively with self-report measures of PTSD symptoms. These results suggest that PTSD patients may be more vigilant for, or primed to respond to, the appearance of angry faces, relative to fearful, but further study is needed.