Sleep disturbance and computerized axial tomographic scan findings in former prisoners of war

Evidence of resilience: neuroimaging in former prisoners of war

In this study, single voxel proton magnetic resonance spectroscopic imaging ((1)H-MRS) and volumetric analysis of hippocampal magnetic resonance imaging (MRI) images were used to determine if any differences in hippocampal biochemistry or volume were present between former prisoners of war (POWs) with and without posttraumatic stress disorder (PTSD) and control subjects matched for age and education. This study did not find lower hippocampal concentrations of N-acetylaspartate (NAA), smaller hippocampal volumes, or more impaired memory function in older veterans with PTSD compared with a group matched for traumatic experience or a nontraumatized control group.

Brain-imaging studies of posttraumatic stress disorder

Brain-imaging studies of posttraumatic stress disorder (PTSD) have rapidly increased in recent years. Structural studies have identified potential smaller volumes of the hippocampus of traumatized and/or PTSD subjects. Functional activation studies have implicated hyperactive or altered functioning of brain regions, such as the amygdala and the insula, and a failure to engage emotional regulatory structures, such as the medial prefrontal and anterior cingulate cortex. Recent neurochemical investigations have suggested that neuromodulatory systems (eg, gamma-aminobutyric acid, micro-opioid) may underlie these aberrant brain activation patterns. This article reviews the literature on structural, functional, and neurochemical brain-imaging studies of PTSD.

To breathe, perchance to sleep: sleep-disordered breathing and chronic insomnia among trauma survivors

Standard psychiatric classification (DSM-IV-TR) traditionally attributes post-traumatic sleep disturbance to a secondary or symptomatic feature of a primary psychiatric disorder. The DSM-IV-TR paradigm, however, has not been validated with objective sleep assessment technology, incorporated nosological constructs from the field of sleep disorders medicine, or adequately addressed the potential for post-traumatic stress disorder (PTSD) sleep problems to manifest as primary, physical disorders, requiring independent medical assessments and therapies. This paradigm may limit understanding of sleep problems in PTSD by promulgating such terms as "insomnia related to another mental disorder," a.k.a. "psychiatric insomnia." Emerging evidence invites a broader comorbidity perspective, based on recent findings that post-traumatic sleep disturbance frequently manifests with the combination of insomnia and a higher-than-expected prevalence of sleep-disordered breathing (SDB). In this model of complex sleep disturbance, the underlying sleep pathophysiology interacts with PTSD and related psychiatric distress; and this relationship appears very important as demonstrated by improvement in insomnia, nightmares, and post-traumatic stress with successful SDB treatment, independent of psychiatric interventions. Continuous positive airway pressure treatment in PTSD patients with SDB reduced electroencephalographic arousals and sleep fragmentation, which are usually attributed to central nervous system or psychophysiological processes. Related findings and clinical experience suggest that other types of chronic insomnia may also be related to SDB. We hypothesize that an arousal-based mechanism, perhaps initiated by post-traumatic stress and/or chronic insomnia, may promote the development of SDB in a trauma survivor and perhaps other patients with chronic insomnia. We discuss potential neurohormonal pathways and neuroanatomatical sites that may be involved in this proposed interaction between insomnia and SDB.

Polysomnographic sleep is not clinically impaired in Vietnam combat veterans with chronic posttraumatic stress disorder

BACKGROUND

Because sleep is typically disturbed in posttraumatic stress disorder (PTSD), this study was undertaken to evaluate a group of Vietnam combat veterans with the disorder using clinical polysomnographic techniques.

METHODS

Eighteen Vietnam combat veterans with PTSD and 10 healthy non-combat-exposed Vietnam era veterans participated in 2 nights of polysomnographic study and a multiple sleep latency test.

RESULTS

No significant differences between subjects and controls were noted except for greater sleep onset latency to stage 2 (p < .03), and lower arousals/hour from stages 3 & 4 (p < .04) on night 2, and lower subjectively estimated total sleep time on night 1 (p < .005) in the case of PTSD subjects. Otherwise, results from the second night served to replicate those from the first, and no significant differences appeared on 2 successive nights for any polysomnographic variable. No daytime hypersomnolence was detected.

CONCLUSIONS

Polysomnographically recorded sleep was notably better than expected in the presence of clinically significant PTSD with typical histories of disrupted sleep. In these subjects, there is no clinically significant sleep disorder or typical pattern of sleep disturbance detectable by standard polysomnography.

Sleep electroencephalographic patterns and cranial computed tomography in anxiety disorders

Sleep electroencephalogram (EEG) and cranial computed tomography (CT) were performed in 15 drug-free inpatients with an anxiety disorder. The sleep EEG of the patients was characterized by a decreased sleep efficiency and a shortened REM latency. Under visual inspection, four (27%) patients showed ventricular enlargement, while an increased ventricular brain ratio (VBR) was measured in five (33%). No clear associations between EEG sleep measures and ventricular size became obvious, although there is good evidence in the literature that sleep continuity, slow-wave sleep, or REM sleep are closely related to ventricular and/or sulcal widening in various neuropsychiatric disorders.

All-night electroencephalographic sleep and cranial computed tomography in depression. A study of unipolar and bipolar patients

All-night electroencephalographic (EEG) sleep recording and cranial computed tomography were performed in 24 inpatients with major depression (14 unipolar, 10 bipolar). The patients showed the characteristic "depression-like" EEG sleep alterations and their ventricular brain ratio (VBR) was increased compared with the control subjects. No major differences were found between the unipolar and the bipolar groups. There was a close and positive association between the VBR values and several measures of slow wave sleep. It is hypothesized that this relationship is due to an altered function of the limbic-hypothalamic-pituitary-adrenocortical axis in depression that affects both EEG sleep and brain morphology.