Effects of traumatic brain injury and posttraumatic stress disorder on Alzheimer's disease in veterans, using the Alzheimer's Disease Neuroimaging Initiative (original) (raw)
Related papers
Military risk factors for Alzheimer's disease
Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are signature injuries of the wars in Iraq and Afghanistan and have been linked to an increased risk of Alzheimer's disease (AD) and other dementias. A meeting hosted by the Alzheimer's Association and the Veterans' Health Research Institute (NCIRE) in May 2012 brought together experts from the U.S. military and academic medical centers around the world to discuss current evidence and hypotheses regarding the pathophysiological mechanisms linking TBI, PTSD, and AD. Studies underway in civilian and military populations were highlighted, along with new research initiatives such as a study to extend the Alzheimer's Disease Neuroimaging Initiative (ADNI) to a population of veterans exposed to TBI and PTSD. Greater collaboration and data sharing among diverse research groups is needed to advance an understanding and appropriate interventions in this continuum of military injuries and neurodegenerative disease in the aging veteran.
Early-Onset Dementia in War Veterans: Brain Polypathology and Clinicopathologic Complexity
Journal of Neuropathology & Experimental Neurology
The neuropathology associated with cognitive decline in military personnel exposed to traumatic brain injury (TBI) and chronic stress is incompletely understood. Few studies have examined clinicopathologic correlations between phosphorylated-tau neurofibrillary tangles, β-amyloid neuritic plaques, neuroinflammation, or white matter (WM) lesions, and neuropsychiatric disorders in veterans. We describe clinicopathologic findings in 4 military veterans with early-onset dementia (EOD) who had varying histories of blunt- and blast-TBI, cognitive decline, behavioral abnormalities, post-traumatic stress disorder, suicidal ideation, and suicide. We found that pathologic lesions in these military-EOD cases could not be categorized as classic Alzheimer’s disease (AD), chronic traumatic encephalopathy, traumatic axonal injury, or other well-characterized clinicopathologic entities. Rather, we observed a mixture of polypathology with unusual patterns compared with pathologies found in AD or oth...
Military-related risk factors for dementia
Alzheimer's & Dementia
Introduction: In recent years, there has been growing discussion to better understand the pathophysiological mechanisms of traumatic brain injury and post-traumatic stress disorder and how they may be linked to an increased risk of neurodegenerative diseases including Alzheimer's disease in veterans. Methods: Building on that discussion, and subsequent to a special issue of Alzheimer's & Dementia published in June 2014, which focused on military risk factors, the Alzheimer's Association convened a continued discussion of the scientific community on December 1, 2016. Results: During this meeting, participants presented and evaluated progress made since 2012 and identified outstanding knowledge gaps regarding factors that may impact veterans' risk for later life dementia. Discussion: The following is a summary of the invited presentations and moderated discussions of both the review of scientific understanding and identification of gaps to inform further investigations.
Traumatic Brain Injury and Early Onset Dementia in Post 9-11 Veterans
Brain Injury
Objectives: The objective of this work was to assess TBI-related risks factors for early-onset dementia (EOD). Background: Young Post-9/11 Veterans may be at elevated risk for EOD because they experience high rates of traumatic brain injury (TBI) in early/mid adulthood. However, few studies have explored the longitudinal relationship between traumatic brain injury (TBI) and the emergence of EOD subtypes. Methods: This matched case-control study used data from the Veterans Health Administration (VHA) to identify Veterans with EOD. To address the low positive predictive value (PPV=0.27) of dementia algorithms in VHA records, we identified Alzheimer's disease (AD) and frontotemporal
NeuroImage. Clinical, 2018
Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are risk factors for early onset of Alzheimer's disease (AD) and may accelerate the progression rate of AD pathology. As amyloid-beta (Aβ) plaques are a hallmark of AD pathology, we hypothesized that TBI and PTSD might increase Aβ accumulation in the brain. We examined PET and neuropsychological data from Vietnam War veterans compiled by the US Department of Defense Alzheimer's Disease Neuroimaging Initiative, to examine the spatial distribution of Aβ in male veterans' who had experienced a TBI and/or developed PTSD. Subjects were classified into controls, TBI only, PTSD only, and TBI with PTSD (TBI_PTSD) groups and data were analyzed using both voxel-based and ROI-based approaches. Compared to controls, all three clinical groups showed a pattern of mainly increased referenced standard uptake values (SUVR) for the amyloid tracer [F]-AV45 PET, with rank order PTSD > TBI_PTSD > TBI > Control, a...
Military Medicine, 2009
Seventy-two veterans with traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), or both participated in assessment procedures to evaluate between group differences. Half the sample was randomly selected for magnetic resonance imaging (MRI). Neurologic examinations were conducted using the Neurologic Rating Scale (NRS). Neuropsychological measures included the Paced Auditory Serial Addition Test (PASAT), Rey Auditory Verbal Learning Test (RAVLT), Conners' Continuous Performance Test II (CPT II), and Halstead Impairment Index (HII) including the Booklet Category Test (BCT).'Data were analyzed using linear regression. Participants with moderate/ severe TBI were significantly more likely to have trauma-related imaging findings, and more severe TBI predicted lower scores on the NRS. No significant between-group differences were identified on the HII, PASAT, RAVLT, or CPT II. TBI group performance was significantly better on the BCT. More severe TBI predicted abnormal imaging findings and lower NRS scores. Hypothesized between-group differences on neuropsychological measures were not supported.
Military risk factors for cognitive decline, dementia and Alzheimer's disease
Current Alzheimer Research, 2013
Delayed neurological health consequences of environmental exposures during military service have been generally underappreciated. The rapidly expanding understanding of Alzheimer's disease (AD) pathogenesis now makes it possible to quantitate some of the likely long-term health risks associated with military service. Military risk factors for AD include both factors elevated in military personnel such as tobacco use, traumatic brain injury (TBI), depression, and post-traumatic stress disorder (PTSD) and other nonspecific risk factors for AD including, vascular risk factors such as obesity and obesity-related diseases (e.g., metabolic syndrome), education and physical fitness. The degree of combat exposure, Vietnam era Agent Orange exposure and Gulf War Illness may also influence risk for AD. Using available data on the association of AD and specific exposures and risk factors, the authors have conservatively estimated 423,000 new cases of AD in veterans by 2020, including 140,000 excess cases associated with specific military exposures. The cost associated with these excess cases is approximately 5.8billionto5.8 billion to 5.8billionto7.8 billion. Mitigation of the potential impact of military exposures on the cognitive function of veterans and management of modifiable risk factors through specifically designed programs will be instrumental in minimizing the impact of AD in veterans in the future decades.
Neurocase, 2008
Posttraumatic stress disorder (PTSD) is associated with decreased hippocampal volume, but the relationship between trauma and brain morphology in the absence of PTSD is less clear. In this study, measures of brain integrity were determined by estimating gray and white matter regional brain volumes using structural magnetic resonance imaging in six patients with PTSD and in five controls with comparable trauma exposure but without clinical evidence of PTSD. The only statistically significant volume difference between groups was observed multivariately in the white matter of the right temporal lobe (superior temporal gyrus, fusiform gyrus, parahippocampal gyrus, white-matter stem, middle temporal gyrus, and inferior temporal gyrus), although small sample sizes limit the power to detect between-group differences. Both groups showed heterogeneity in cerebral atrophy.
World journal of nuclear medicine, 2022
Purpose Incidence of early onset neurocognitive dysfunction has been reported in World Trade Center (WTC) responders. Ongoing studies are investigating the underlying etiology, as we are concerned that an underlying risk of neurodegenerative dementia may be occurring because of their stressful and neurotoxic exposures to particulate matter when they responded to the search and rescue efforts on September 11, 2001. The purpose of this study is to report preliminary results from two ongoing positron emission tomography (PET)/magnetic resonance imaging (MRI) imaging studies investigating the presence of Alzheimer's disease (AD) biomarkers, such as β-amyloid, tau, and neurodegeneration, and compare our findings to published norms. Methods We present findings on 12 WTC responders diagnosed with either cognitive impairment (CI) or mild cognitive impairment (MCI), now at midlife, who underwent PET/MRI brain imaging as part of ongoing studies. Six responders with CI received [ 18 F] florbetaben (FBB) to detect β-amyloidosis and six separate responders with MCI
NeuroRehabilitation, 2013
To characterize the clinical profiles of individuals with dementia who do and do not report a history of TBI. Some evidence suggests that a history of traumatic brain injury (TBI) is associated with an increased risk of dementia later in life. The clinical features of dementia associated with TBI have not been well investigated. While there is some evidence that TBI is associated with increased risk of Alzheimer's disease (AD), there are also indications that dementia associated with TBI has prominent behavioral, affective, and motor symptoms, making it distinct from AD. The current study involves secondary analysis of baseline data from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS). Individuals with dementia who reported a history of TBI had higher fluency and verbal memory scores and later onset of decline, but they are on more medications, had worse cardiovascular and cerebrovascular health, were more likely to have received medical attention ...