Hippocampal volume in adult burn patients with and without posttraumatic stress disorder

OBJECTIVE: Increasing evidence suggests that posttraumatic stress disorder (PTSD) is associated with small hippocampal size. The authors compared trauma-exposed subjects with PTSD and trauma-exposed subjects without PTSD to clarify whether small hippocampal size is related to PTSD or to mere trauma exposure. METHOD: Three-dimensional structural magnetic resonance imaging was used to assess hippocampal volumes in 30 men who had recently been exposed to a severe burn trauma and 15 matched healthy comparison subjects. RESULTS: Relative to the comparison subjects, the trauma-exposed subjects with PTSD (N=15) as well as the trauma-exposed subjects without PTSD (N=15) had significantly smaller volumes of the right hippocampus (subjects with PTSD: -12%; subjects without PTSD: -13%). Larger total areas of burned body surface were significantly related to smaller left hippocampal volumes. Use of analgesic/sedative treatment with the N-methyl-d-aspartic acid (NMDA) antagonist ketamine was significantly related to larger right hippocampal volumes and to stronger PTSD symptoms. CONCLUSIONS: PTSD is not a necessary condition for small hippocampal size in trauma-exposed individuals. Rather, the results provide evidence that smaller hippocampal size in trauma-exposed individuals is a result of traumatic stress. The posttraumatic application of NMDA antagonists may protect against hippocampal damage induced by traumatic stressors but increases the patient's risk of developing PTSD symptoms.     

Smaller hippocampal volume in patients with recent-onset posttraumatic stress disorder.

BACKGROUND: Previous structural magnetic resonance (MR) research in patients with posttraumatic stress disorder (PTSD) has found smaller hippocampal volumes in patients compared with control subjects. These studies have mostly involved subjects who have had PTSD for a number of years, such as war veterans or adult survivors of childhood abuse. Patients with recent-onset PTSD have rarely been investigated. To our knowledge only one other study has investigated such a group. The aim of this study was to compare hippocampal volumes of patients with recent onset PTSD and nontrauma-exposed control subjects. METHODS: Fifteen patients with PTSD, recruited from an accident and emergency department, were compared with 11, non-trauma-exposed, healthy control subjects. Patients underwent a structural MR scan soon after trauma (mean time = 158 +/- 41 days). Entire brain volumes, voxel size 1 x 1 x 1 mm, were acquired for each subject. Point counting and stereology were used to measure the hippocampal and amygdala volume of each subject. RESULTS: Right-sided hippocampal volume was significantly smaller in PTSD patients than control subjects after controlling for effects of whole brain volume and age. Neither left nor total hippocampal volume were significantly smaller in the PTSD group after correction. Whole brain volume was also found to be significantly smaller in patients. There were no differences in amygdala or white matter volumes between patients and control subjects. CONCLUSIONS: This result replicates previous findings of smaller hippocampal volumes in PTSD patients, but in an underinvestigated population, suggesting that either smaller hippocampal volume is a predisposing factor in the development of PTSD or that damage occurs within months of trauma, rather than a number of years. Either of these two hypotheses have significant implications for the treatment of PTSD. For instance, if it could be shown that screening for hippocampal volume may, in some cases, predict those likely to develop clinical PTSD.     

Automated measurement of hippocampal subfields in PTSD: Evidence for smaller dentate gyrus volume

Smaller hippocampal volume has been consistently observed as a biomarker of posttraumatic stress disorder (PTSD). However, less is known about individual volumes of the subfields composing the hippocampus such as the dentate gyrus and cornu ammonis (CA) fields 1–4 in PTSD. The aim of the present study was to examine the hypothesis that volume of the dentate gyrus, a region putatively involved in distinctive encoding of similar events, is smaller in individuals with PTSD versus trauma-exposed controls. Ninety-seven recent war veterans underwent structural imaging on a 3T scanner and were assessed for PTSD using the Clinician-Administered PTSD Scale. The hippocampal subfield automated segmentation program available through FreeSurfer was used to segment the CA4/dentate gyrus, CA1, CA2/3, presubiculum, and subiculum of the hippocampus. Results showed that CA4/dentate gyrus subfield volume was significantly smaller in veterans with PTSD and scaled inversely with PTSD symptom severity. These results support the view that dentate gyrus abnormalities are associated with symptoms of PTSD, although additional evidence is necessary to determine whether these abnormalities underlie fear generalization and other memory alterations in PTSD.     

Hippocampal volume deficits associated with exposure to psychological trauma and posttraumatic stress disorder in adults: A meta-analysis

Trauma exposure itself in the absence of posttraumatic stress disorder (PTSD) may be associated with hippocampal volume deficits. We meta-analytically compared hippocampal volumes in PTSD subjects, in trauma-exposed subjects without PTSD, and in trauma-unexposed subjects. Using the words and phrases PTSD, neuroimaging, hippocampus, brain, violence, trauma, abuse, rape, war, combat, accident, and disaster, we searched major computerized databases to obtain candidate studies through 2008 for inclusion. We identified 39 hippocampal volumetric studies in adults with PTSD compared to control groups consisting of either trauma-exposed controls without PTSD or trauma-unexposed controls, or both. We meta-analytically compared left, right, and total hippocampal volumes between 1) PTSD subjects and a trauma-unexposed group, 2) PTSD subjects and a trauma-exposed group without PTSD, and 3) a trauma-unexposed group and a trauma-exposed group without PTSD. Hippocampal volumes were smaller in the PTSD group and trauma-exposed group without PTSD compared to the trauma-unexposed group. Further, the right hippocampus was smaller in the PTSD group compared to the trauma-exposed group without PTSD. Additionally, the right hippocampus was larger than the left in the PTSD and trauma-unexposed groups but not in the trauma-exposed group without PTSD. Hippocampal volume reduction is associated with trauma exposure independent of PTSD diagnosis, albeit additional hippocampal reduction was found in PTSD compared to the trauma-exposed group without PTSD.     

Hippocampal volume in aging combat veterans with and without post-traumatic stress disorder: relation to risk and resilience factors

OBJECTIVE: To examine whether there are post-traumatic stress disorder (PTSD) related differences in hippocampal volume in middle-aged and elderly veterans and to examine the relationship of neuroendocrine activity, memory performance, and measures of risk and resilience for PTSD to hippocampal volume in this cohort. METHODS: Seventeen veterans with chronic PTSD and 16 veterans without chronic PTSD received an MRI scan followed by neuroendocrine assessment (24-h urinary cortisol excretion and the lysozyme IC(50-DEX), a measure of glucocorticoid receptor (GR) responsiveness), and cognitive testing. RESULTS: Veterans with PTSD did not differ from those without PTSD in hippocampal volume, but they did show significantly lower urinary cortisol levels, and poorer memory performance on the Wechsler Logical Memory test and Digit Span test. Smaller left hippocampal volumes were observed in veterans who developed PTSD in response to their first reported traumatic exposure, compared to veterans who had first experienced a traumatic event to which they did not develop PTSD, prior to experiencing a subsequent event that led to PTSD. In contrast, the two neuroendocrine measures were associated with risk factors related to early trauma exposure. CONCLUSION: Although hippocampal volume was not found to differ between subjects with and without PTSD, smaller hippocampal volumes in PTSD may be associated with specific risk and resilience factors. These may be distinct from vulnerability markers associated with increased responsiveness to glucocorticoids and/or other neuroendocrine measures that have been observed in combat-related PTSD.     

Magnetic resonance imaging volumes of the hippocampus in drug-naïve patients with post-traumatic stress disorder without comorbidity conditions

Most brain imaging studies have showed smaller hippocampal volume in adults with chronic PTSD; however, some other studies have not replicated this finding. Most of these investigations included subjects with other psychiatric comorbidities, such as major depression or alcohol abuse.

The prevalence of psychiatric comorbidities in PTSD is generally high and this makes it difficult, if not impossible, to disentangle the contribution of other disorders to hippocampal volume.

Therefore, the main goal of the current study is to compare hippocampal volumes of healthy subjects and drug-naïve patients with PTSD caused by different types of mixed civilian traumas (i.e. car accident, physical abuse, sudden death of a family member, assault or robbery, natural disaster and traumatic abortion) and without comorbidity conditions.

Magnetic resonance imaging (MRI) was used to measure the hippocampi, total cerebrum, gray matter, white matter and cerebrospinal fluid volumes in 34 patients with single diagnosis of PTSD, and 34 case-matched non-PTSD comparison subjects.

The patients with single diagnosis of PTSD had an 11.8% smaller left hippocampus (p < 0.001) and an 8.7% smaller right hippocampus (p = 0.003) than the healthy controls. The results were controlled for the total brain volume and for gray matter volumes. Subjects with PTSD also displayed lower overall gray matter volume (p = 0.006).

There were no significant correlations between hippocampal volumes and illness duration or severity of PTSD. The findings indicate the presence of smaller hippocampal volumes in drug-naïve patients with single diagnosis of PTSD, compared with healthy subjects.     

Alterations in hippocampal subfield and amygdala subregion volumes in posttraumatic subjects with and without posttraumatic stress disorder

The hippocampus and amygdala are important structures in the posttraumatic stress disorder (PTSD); however, the exact relationship between these structures and stress or PTSD remains unclear. Moreover, they consist of several functionally distinct subfields/subregions that may serve different roles in the neuropathophysiology of PTSD. Here we present a subregional profile of the hippocampus and amygdala in 145 survivors of a major earthquake and 56 non‐traumatized healthy controls (HCs). We found that the bilateral hippocampus and left amygdala were significantly smaller in survivors than in HCs, and there was no difference between survivors with (n = 69) and without PTSD (trauma‐exposed controls [TCs], n = 76). Analyses revealed similar results in most subfields/subregions, except that the right hippocampal body (in a head‐body‐tail segmentation scheme), right presubiculum, and left amygdala medial nuclei (Me) were significantly larger in PTSD patients than in TCs but smaller than in HCs. Larger hippocampal body were associated with the time since trauma in PTSD patients. The volume of the right cortical nucleus (Co) was negatively correlated with the severity of symptoms in the PTSD group but positively correlated with the same measurement in the TC group. This correlation between symptom severity and Co volume was significantly different between the PTSD and TCs. Together, we demonstrated that generalized smaller volumes in the hippocampus and amygdala were more likely to be trauma‐related than PTSD‐specific, and their subfields/subregions were distinctively affected. Notably, larger left Me, right hippocampal body and presubiculum were PTSD‐specific; these could be preexisting factors for PTSD or reflect rapid posttraumatic reshaping.     

Smaller head of the hippocampus in Gulf War-related posttraumatic stress disorder

Reductions in hippocampal volume and impairment in short-term verbal memory have been reported in Vietnam combat veterans with posttraumatic stress disorder (PTSD) and in women with abuse-related PTSD. The present investigation evaluated hippocampal volume and memory in Gulf War veterans. This research is timely given the ongoing war in Iraq and the anticipated high rates of PTSD among returning combat soldiers. Fourteen veterans with PTSD related to traumatic experiences during the Gulf War (1990-1991), 23 deployed veterans without PTSD, 22 non-deployed reservists and 29 healthy civilians were studied. Volumes of the hippocampus, temporal lobe, and whole brain were measured on coronal MRI scans, and hippocampal mediated memory function was evaluated. The head of the hippocampus was the only subregion that was significantly smaller in Gulf War veterans with PTSD than in healthy civilians. Deployed veterans with PTSD, deployed veterans without PTSD, and non-deployed reservists had significantly smaller whole hippocampal volume and lower scores on immediate and delayed verbal and visual retrieval compared with healthy civilians.     

The atrophy and laterality of the hippocampal subfields in parents with or without posttraumatic stress disorder who lost their only child in China

Investigating hippocampal subfields may provide new and important insights into the pathophysiology of posttraumatic stress disorder (PTSD). However, no study has examined the hippocampal subfield volume changes in parents with or without PTSD who had lost their only child and could no longer conceive in China. Fifty-seven parents with PTSD (PTSD+), 11 trauma-exposed parents without PTSD (PTSD?), and 39 non-traumatized controls were recruited to examine the hippocampal subfield volumes using magnetic resonance imaging. Correlations of the volumes with the time since trauma and Clinician-Administered PTSD Scale (CAPS) scores were investigated in the PTSD+ group. The volumes of the bilateral cornu ammonis (CA) 2–3, CA4–dentate gyrus (DG), and left subiculum were significantly smaller in the PTSD+ and PTSD? groups than in the controls, but there were no significant differences between the PTSD+ and PTSD? groups. Additionally, the left CA2–3 and CA4–DG volumes reduced more than those on the right side in the PTSD+ and PTSD? groups. The subfield volumes were not related to the time since trauma and the CAPS scores in the PTSD+ group. In conclusion, hippocampal subfield volumes decreased in parents who lost their only child with or without PTSD, and the volumetric reduction may be independent of PTSD and trauma-related. Moreover, the hippocampal volume deficits showed laterality that the left side was affected more than the right, and the hippocampal subfields may show differential vulnerabilities to trauma/PTSD, with the CA2–3 and CA4–DG subfields more sensitive than others.     

Single-voxel proton MR spectroscopy of right versus left hippocampi in PTSD

Previous magnetic resonance (MR) volume imaging and proton MR spectroscopy studies have suggested a reduction in the hippocampal size and/or neuronal/axonal density in posttraumatic stress disorder (PTSD). The lack of agreement on the laterality of the hippocampal dysfunction prompted this study. A total of 20 veterans (18 men and two women) and one female non-veteran participated in this study conducted in accordance with approved human study protocols. Six of the male veterans and the female non-veteran were without PTSD. Vietnam veterans formed a large subset of the study subjects. Single-voxel proton MR spectra were obtained from the hippocampal region bilaterally on a clinical MR scanner operating at 1.5 T. Analysis of the proton MR spectra showed a decrease in hippocampal NAA/creatine ratio in PTSD subjects significantly higher on the left than the right for the entire study group, as well as for the Vietnam subset. It was concluded that the hippocampal dysfunction in PTSD is lateralized with the left side being more impaired than the right.     

Extratemporal atrophy in patients with complex partial seizures of left temporal origin

Total cerebral, temporal lobe, hippocampal, caudate, and lenticular nuclei volumes were quantified from magnetic resonance images of 21 patients with left temporal lobe epilepsy and medically intractable complex partial seizures. These regional brain volumes were compared with the same measures in 19 controls. No significant differences in total cerebral, left temporal lobe, right temporal lobe, or total temporal lobe volumes were found. As expected, left hippocampal volumes were significantly smaller in the patients with epilepsy than in control subjects. The left hippocampus-to-right hippocampus volume ratio was significantly lower in patients than in control subjects. In addition to left hippocampal volumes, mean left thalamic, left caudate, and bilateral lenticular volumes were significantly smaller in the patients with epilepsy than in control subjects. The left-to-right thalamic volume ratio was also significantly lower in the patients with epilepsy compared with control subjects, but there were no significant group differences in caudate or lenticular ratios. These results show that medically intractable temporal lobe epilepsy is associated with volume loss in brain structures outside the presumably involved hippocampus. The pathophysiological significance of our findings is uncertain. They could be related to the underlying cause of the disorder. However, volume loss also may reflect damage due to involvement of these structures in recurrent seizure activity.     

Hippocampal volume in patients with alcohol dependence

BACKGROUND: Smaller hippocampal volumes have been reported in the brains of alcoholic patients than in those of healthy subjects, although it is unclear if the hippocampus is disproportionally smaller than the brain as a whole. There is evidence that alcoholic women are more susceptible than alcoholic men to liver and cardiac damage from alcohol. It is not known whether the hippocampi of the female brain are more vulnerable to alcohol. METHODS: We compared the hippocampal volumes in 52 hospitalized alcoholic men and women with those of 36 healthy nonalcoholic men and women. All subjects were between 27 and 53 years of age. The hippocampal volumes were measured from sagittal T-weighted high-resolution magnetic resonance images. RESULTS: The alcoholic women had less lifetime drinking and a later age at onset of heavy drinking than alcoholic men. Both alcoholic men and women had significantly smaller right hippocampi and larger cerebrospinal fluid volumes than healthy subjects of the same sex. Only among women were the left hippocampus and the nonhippocampal brain volume also significantly smaller. The proportion of hippocampal volume relative to the rest of the brain volume was the same in alcoholic patients and healthy subjects, in both men and women. The right hippocampus was larger than the left among all subjects. Women demonstrated larger hippocampal volumes relative to total brain volume than men. Psychiatric comorbidity, including posttraumatic stress disorder, did not affect hippocampal volume. CONCLUSIONS: In chronic alcoholism, the reduction of hippocampal volume is proportional to the reduction of the brain volume. Alcohol consumption should be accounted for in studies of hippocampal damage.     

Absence of hippocampal volume differences in survivors of the Nazi Holocaust with and without posttraumatic stress disorder

It remains unclear whether smaller hippocampal volume is a consistent feature of chronic posttraumatic stress disorder (PTSD) and whether it accounts for the associated memory deficits observed in this illness. Hippocampal volume, comparison regions and memory performance were examined in Holocaust survivors with PTSD (PTSD+: n=14; 5 men, 9 women) and without PTSD (PTSD-: n=13; 6 men, 7 women) and a non-exposed control group of healthy Jewish adults (n=20; 13 men, 7 women). The subjects had medical examinations, high-resolution magnetic resonance imaging, and memory testing. PTSD+ subjects had poorer memory performance than non-exposed subjects and PTSD- subjects, but they did not differ from either group in right or left hippocampal volume when gender and head size were taken into account. Older age and smaller left hippocampal volume were more strongly associated in the PTSD+ group than in the PTSD- groups. Holocaust survivors had larger superior temporal gyral and lateral temporal lobe volumes bilaterally than non-exposed subjects. Smaller hippocampal volume is not invariably associated with chronic PTSD and does not explain the substantial explicit memory impairment observed in Holocaust survivors with this disorder. Larger temporal lobe volumes may be associated with early traumatization and survival or may reflect some other characteristic of Holocaust survivors.     

Hippocampal function in posttraumatic stress disorder

Recent studies have reported memory deficits and reduced hippocampal volumes in posttraumatic stress disorder (PTSD). The goal of the current research was to use functional neuroimaging and a validated explicit memory paradigm to examine hippocampal function in PTSD. We used positron emission tomography (PET) and a word-stem completion task to study regional cerebral blood flow (rCBF) in the hippocampus in 16 firefighters: 8 with PTSD (PTSD group) and 8 without PTSD (Control group). During PET scanning, participants viewed three-letter word stems on a computer screen and completed each stem with a word they had previously encoded either deeply (High Recall condition) or shallowly (Low Recall condition). Relative to the Control group, the PTSD group exhibited significantly smaller rCBF increases in the left hippocampus in the High vs Low Recall comparison. However, this finding reflected relatively elevated rCBF in the Low Recall condition in the PTSD group. Collapsing across High and Low Recall conditions, (1) the PTSD group had higher rCBF in bilateral hippocampus and left amygdala than the Control group, and (2) within the PTSD group, symptom severity was positively associated with rCBF in hippocampus and parahippocampal gyrus. The groups did not significantly differ with regard to accuracy scores on the word-stem completion task. The PTSD group had significantly smaller right (and a trend for smaller left) hippocampal volumes than the Control group. The results suggest an abnormal rCBF response in the hippocampus during explicit recollection of nonemotional material in firefighters with PTSD, and that this abnormal response appears to be driven by relatively elevated hippocampal rCBF in the comparison condition.     

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.     

Hippocampal and amygdala volumes in children and adults with childhood maltreatment-related posttraumatic stress disorder: a meta-analysis

Little work has directly examined the course of hippocampal volume in children and adults with childhood maltreatment-related posttraumatic stress disorder (PTSD). Data from adults suggest that hippocampal volume deficits are associated with PTSD, whereas findings from children with PTSD generally show no hippocampal volume deficits in PTSD. Additionally, the role of the amygdala in emotional response makes it a possible region for investigation in children and adults with childhood maltreatment-related PTSD. The objectives of this study were 2-fold: (1) to meta-analytically determine whether hippocampal and amygdala volumes in children and adults with PTSD from childhood maltreatment differ from those in healthy controls, and (2) to use cross-sectional findings performed with meta-analyses as a proxy for longitudinal studies to estimate the course of hippocampal and amygdala volumes in child and adult subjects with PTSD from childhood maltreatment. Using electronic databases, we identified articles containing hippocampal and amygdala data for children with PTSD and adults with PTSD from childhood maltreatment. Data were extracted and effect sizes were calculated using Comprehensive Meta-Analysis Version 2.0. Reduced bilateral hippocampal volume was found in adults with childhood maltreatment-related PTSD compared with healthy controls, but this deficit was not seen in children with maltreatment-related PTSD, suggesting hippocampal volume deficits from childhood maltreatment may not be apparent until adulthood. Greater left than right hippocampal volume was found in the adult healthy control group but not in the PTSD group. Amygdala volume in children with maltreatment-related PTSD did not differ from that in healthy controls. Hippocampal volume is normal in children with maltreatment-related PTSD but not in adults with PTSD from childhood maltreatment, suggesting an initially volumetrically normal hippocampus with subsequent abnormal volumetric development occurring after trauma exposure. However, longitudinal studies are needed to support these preliminary findings.     

Cortisol levels are positively correlated with hippocampal N-acetylaspartate.

BACKGROUND: This study examined the relationship of hypothalamic-pituitary-adrenal measures and hippocampal N-acetylaspartate (NAA) in posttraumatic stress disorder (PTSD) patients and control subjects. METHODS: Eleven patients with combat-related PTSD and 11 control subjects were evaluated with magnetic resonance spectroscopy as well as by morning salivary cortisol samples before and after administration of low-dose dexamethasone (.5 mg). RESULTS: Left hippocampal NAA was strongly associated with both pre-dexamethasone cortisol levels (n = 22, r =.53, p =.013) and post-dexamethasone cortisol levels (n = 22, r =.63, p =.002). After accounting for clinical symptom severity and hippocampal volume, cortisol levels accounted for 21.9% of the variance (F = 5.6, p =.004) in left hippocampal NAA and 12.6% of the variance (F = 3.2, p =.035) in right hippocampal NAA. CONCLUSIONS: This study shows a positive relationship between cortisol levels and hippocampal NAA in subjects without hypercortisolemia. Within the range of values seen in our subjects, cortisol may have a trophic effect on the hippocampus.     

Abnormal hippocampal morphology in dissociative identity disorder and post‐traumatic stress disorder correlates with childhood trauma and dissociative symptoms

Smaller hippocampal volume has been reported in individuals with post‐traumatic stress disorder (PTSD) and dissociative identity disorder (DID), but the regional specificity of hippocampal volume reductions and the association with severity of dissociative symptoms and/or childhood traumatization are still unclear. Brain structural magnetic resonance imaging scans were analyzed for 33 outpatients (17 with DID and 16 with PTSD only) and 28 healthy controls (HC), all matched for age, sex, and education. DID patients met criteria for PTSD (PTSD–DID). Hippocampal global and subfield volumes and shape measurements were extracted. We found that global hippocampal volume was significantly smaller in all 33 patients (left: 6.75%; right: 8.33%) compared with HC. PTSD–DID (left: 10.19%; right: 11.37%) and PTSD‐only with a history of childhood traumatization (left: 7.11%; right: 7.31%) had significantly smaller global hippocampal volume relative to HC. PTSD–DID had abnormal shape and significantly smaller volume in the CA2‐3, CA4‐DG and (pre)subiculum compared with HC. In the patient groups, smaller global and subfield hippocampal volumes significantly correlated with higher severity of childhood traumatization and dissociative symptoms. These findings support a childhood trauma‐related etiology for abnormal hippocampal morphology in both PTSD and DID and can further the understanding of neurobiological mechanisms involved in these disorders. Hum Brain Mapp 36:1692–1704, 2015. © 2014 Wiley Periodicals, Inc.     

Hippocampus and amygdalar volumes in patients with refractory obsessive-compulsive disorder

Functional and structural neuroimaging studies have implicated the hippocampus-amygdala complex in the pathophysiology of obsessive-compulsive disorder (OCD), although no consensus has been established. These brain regions have not been investigated in refractory OCD patients. Volumes of the hippocampus, and amygdala were measured by magnetic resonance imaging (MRI) in a sample of 14 refractory OCD patients and 14 healthy comparison subjects. The mean left and right hippocampal and amygdala volumes of the patients were smaller than those of the healthy controls. OCD severity was not correlated with amygdala volumes but was related to the left hippocampus. Duration of illness was correlated with both hippocampus and left amygdala. Our findings suggest that hippocampus and amygdalar abnormalities can be considered in refractoriness to OCD.     

Combat-related PTSD and psychosocial adjustment problems among substance abusing veterans

The purpose of this study were the following: a) to determine the prevalence of combat-related posttraumatic stress disorder (PTSD) symptoms among veterans seeking assistance at a Veterans Administration medical center substance abuse treatment facility, b) to examine the relative contribution of Vietnam war zone variables to PTSD symptom development, and c) to study psychosocial adjustment problems associated with Vietnam combat exposure and with PTSD symptoms among help-seeking substance abusing men. Of 489 male veterans presenting for treatment, 10.7% had significant Vietnam combat-related PTSD symptoms as measured by the Mississippi Scale for Combat-Related PTSD. Clinically significant PTSD symptoms occurred among 46% of the subsample of combat-exposed Vietnam veterans with substance abuse problems. Degree of combat exposure was the most important military stressor that distinguished Vietnam veterans with PTSD from those without PTSD, but the groups also differed on age of war zone duty, duration of war zone duty, and whether they were wounded. Veterans who served in Vietnam did not differ from veterans who had no war zone duty on various parameters of psychosocial adjustment. However, the subgroup of Vietnam veterans with PTSD symptoms reported significantly greater psychosocial adjustment problems than their counterparts who did not have PTSD. The deleterious effects associated with combat-related PTSD appeared to be confined to adjunctive psychiatric difficulties and unemployment and did not increase risk of arrests for antisocial conduct beyond that found for veterans without PTSD. Methodological and clinical implications of these findings are discussed.