Posttraumatic Stress Disorder and Risk For Dementia

Abstract

AbstractBackgroundAccumulating evidence demonstrates that PTSD is associated with higher risk for neurodegenerative disorders. However, the mechanism which drives this relationship and the question of whether the increased risk pertains to the full spectrum of all neurodegenerative disorders is not known. Given that neurodegeneration, as with most illnesses, is caused by complex gene by environment factors, PTSD may be an important disorder to study given that trauma exposure is a large impact environmental exposure.MethodThis presentation will start with a brief review of prospective epidemiologic studies that examine the potential bidirectional relationship between PTSD and dementia disorders. Next, data from the Department of Defense Alzheimer’s Disease Neuroimaging Initiative (DoD ADNI) on amyloid and tau PET imaging in older Vietnam veterans will be presented.ResultData from multiple prospective studies show that having a diagnosis of PTSD is associated with higher risk of subsequent dementia. Further, evidence suggests that PTSD is associated with elevated risk for all types of neurodegenerative disorders including Parkinson’s Disease, though there may be a stronger link to Frontotemporal and Vascular Dementias. Results from a sample 289 non‐demented veterans with PTSD and/or TBI and controls in the DoD ADNI cohort did not show evidence of higher cortical amyloid or tau burden. PTSD was associated with higher prevalence of mild cognitive impairment but in the absence of elevated biomarkers of Alzheimer’s Disease.ConclusionThere are many important questions that need to be resolved to understand what mechanistic pathways for neurodegeneration are facilitated by PTSD. If results from the DoD ADNI study generalize, then future work should focus on whether PTSD increases risk for non‐AD tauopathies or synucleinopathies. Further, the strong association of PTSD with chronic sleep disturbance and elevated pro‐inflammatory cytokines also suggest that need to focus on these candidate mechanisms for accounting for the link between traumatic stress exposure and the development of neurodegenerative disorders.