Dawson W. Hedges

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.

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.

Reduced hippocampal volume in alcohol and substance naïve Vietnam combat veterans with posttraumatic stress disorder.

ObjectiveThis pilot study was undertaken to exclude the effects of alcohol and other substances on brain morphology in posttraumatic stress disorder. BackgroundPosttraumatic stress disorder and alcohol use are among the conditions associated with decreased hippocampal volume. The possible confounding contribution of alcohol and other substances of abuse to decreased hippocampal volume in posttraumatic stress disorder has not been previously explored directly. MethodIn this pilot study, magnetic resonance imaging scans of 4 substance naive subjects with combat-related posttraumatic stress disorder and of 4 controls were quantified. ResultsBilateral hippocampal volumes were significantly smaller in posttraumatic stress disorder subjects. No significant differences were found between posttraumatic stress disorder subjects and the comparison group for total brain, gray and white matter, and ventricular volumes. ConclusionsThese findings suggest that posttraumatic stress disorder in the absence of alcohol and other substance abuse may be associated with reduced hippocampal volume. The significance of reduced hippocampal volume in posttraumatic stress disorder is discussed.

Prevalence of Traumatic Brain Injury in the General Adult Population: A Meta-Analysis

Traumatic brain injury (TBI) is a significant public-health concern. To understand the extent of TBI, it is important to assess the prevalence of TBI in the general population. However, the prevalence of TBI in the general population can be difficult to measure because of differing definitions of TBI, differing TBI severity levels, and underreporting of sport-related TBI. Additionally, prevalence reports vary from study to study. In this present study, we used meta-analytic methods to estimate the prevalence of TBI in the adult general population. Across 15 studies, all originating from developed countries, which included 25,134 adults, 12% had a history of TBI. Men had more than twice the odds of having had a TBI than did women, suggesting that male gender is a risk factor for TBI. The adverse behavioral, cognitive and psychiatric effects associated with TBI coupled with the high prevalence of TBI identified in this study indicate that TBI is a considerable public and personal-health problem.

Prevalence of traumatic brain injury in incarcerated groups compared to the general population: A meta-analysis

Traumatic brain injury can cause numerous behavioral abnormalities including aggression, violence, impulsivity, and apathy, factors that can be associated with criminal behavior and incarceration. To better characterize the association between traumatic brain injury and incarceration, we pooled reported frequencies of lifetime traumatic brain injury of any severity among incarcerated samples and compared the pooled frequency to estimates of the lifetime prevalence of traumatic brain injury in the general population. We found a significantly higher prevalence of traumatic brain injury in the incarcerated groups compared to the general population. As such, there appears to be an association between traumatic brain injury and incarceration.

Early-life stress and cognitive outcome

RationaleEarly-life stress is associated with later neuropsychiatric illness. While the association between early-life stress and brain development is well recognized, relatively few studies have examined the association between exposure to early-life stress and cognitive outcome.ObjectivesThe objective of this paper is to examine the association between early-life stress and cognitive outcome in animal models and humans.MethodsIn this article, we review alterations in cognitive function associated with early-life stress in animals and then discuss the association of early-life stress and cognitive function in humans.ResultsFindings suggest that early-life stress is associated with abnormal cognitive function in animals and humans. Furthermore, cognitive deficits associated with exposure to early-life stress in humans may persist into at least early adulthood, although animal models of enriched environments and studies of children adopted from institutionalized care into foster families suggest that certain social factors may at least partially reverse cognitive deficits following exposure to early-life stress.ConclusionsExposure to stress in early life may be associated with later deficits in cognitive function.

The efficacy of selective serotonin reuptake inhibitors in adult social anxiety disorder : a meta-analysis of double-blind, placebo-controlled trials

Social anxiety disorder is associated with impairment in social and occupational functioning, significant personal distress and a possible economic burden, resulting in a reduction in quality of life. To understand better the efficacy of selective serotonin reuptake inhibitors in social anxiety disorder, randomized, double-blind, placebo-controlled trials were evaluated. Pubmed and PsychINFO electronic databases were searched for social anxiety disorder, social phobia, selective serotonin reuptake inhibitors, citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine and sertraline. Fifteen published, randomized, double-blind, placebo-controlled trials of selective serotonin reuptake inhibitors in social anxiety disorder were identified. Design, subject number, drug and dose, trial length, rating instruments, and baseline and end point data were extracted and then verified independently by a second investigator. Effect sizes were calculated from mean changes in drug and placebo groups in the Liebowitz Social Anxiety Scale and the Sheehan Disability Scale, as well as from other scales where available. For the binary data of the Clinical Global Impression of Change scores, Θlog-odds ratios (the effect-size measure appropriate for binary data) were calculated from proportion changes. Effect sizes for the Liebowitz Social Anxiety Scale ranged from -0.029 to 1.214. Effect sizes for the Sheehan Disability Scale ranged from 0.203 to 0.480 for work, 0.237 to 0.786 for social function, and 0.118 to 0.445 for family function. ΘThe log-odds ratios for Clinical Global Impression of Change scores ranged from 0.644 to 3.267. Consistent with previous studies, selective serotonin reuptake inhibitors appear more effective than placebo for social anxiety disorder, with improvement extending into social and occupational function.

Scrupulosity disorder: An overview and introductory analysis

Scrupulosity is a psychological disorder primarily characterized by pathological guilt or obsession associated with moral or religious issues that is often accompanied by compulsive moral or religious observance and is highly distressing and maladaptive. This paper provides a comprehensive overview of scrupulosity and an original conceptualization of the disorder based on an exhaustive literature review to increase awareness of the disorder among practicing clinicians and stimulate further research. It explores the clinical features of scrupulosity, classified as cognitive, behavioral, affective, and social features, as well as the epidemiology, etiology, and treatment of the disorder. Additionally, it is suggested that scrupulosity, despite its similarity to OCD, may merit a distinctive diagnosis, particularly considering its unique constellation and severity of symptoms and its treatment refractoriness, as supported by statistical analysis.

Caffeine-induced psychosis

As a competitive adenosine antagonist, caffeine affects dopamine transmission and has been reported to worsen psychosis in people with schizophrenia and to cause psychosis in otherwise healthy people. We report of case of apparent chronic caffeine-induced psychosis characterized by delusions and paranoia in a 47-year-old man with high caffeine intake. The psychosis resolved within 7 weeks after lowering caffeine intake without use of antipsychotic medication. Clinicians might consider the possibility of caffeinism when evaluating chronic psychosis.

Reaffirmed Limitations of Meta-Analytic Methods in the Study of Mild Traumatic Brain Injury: A Response to Rohling et al.

In 2009 Pertab, James, and Bigler published a critique of two prior meta-analyses by Binder, Rohling, and Larrabee (1997) and Frencham, Fox, and Maybery (2005) that showed small effect size difference at least 3 months post-injury in individuals who had sustained a mild traumatic brain injury (mTBI). The Binder et al. and Frencham et al. meta-analyses have been widely cited as showing no lasting effect of mTBI. In their critique Pertab et al. (2009) point out many limitations of these two prior meta-analyses, demonstrating that depending on how inclusion/exclusion criteria were defined different meta-analytic findings occur, some supporting the persistence of neuropsychological impairments beyond 3 months. Rohling et al. (2011) have now critiqued Pertab et al. (2009). Herein we respond to the Rolling et al. (2011) critique reaffirming the original findings of Pertab et al. (2009), providing additional details concerning the flaws in prior meta-analytic mTBI studies and the effects on neuropsychological performance.