Autonomic Dysfunction, Brain Blood Flow, and Cognitive Decline in Veterans with Gulf War Illness
Abstract
Gulf War Illness (GWI) is a multi-symptom illness with unknown etiology. GWI is a leading cause of disability in Gulf War Veterans. Cognitive complaints are a common symptom of GWI, which suggests the brain is involved in the development of this condition. As Veterans age, these cognitive complaints may worsen and be compounded by the aging process. GWI may be a condition of “accelerated” brain aging. Therefore, there may be long-term consequences of GWI, and the presence of GWI may increase a person’s risk for developing Alzheimer’s disease (AD) or other dementias. In comparison to other brain-related diseases such as stroke, relatively little is known about GWI and how this condition impacts the normal age-related changes in the brain. To date, there have only been a few studies to systematically evaluate brain structure and function in GWI. Most research on GWI has focused heavily on the psychological aspects of the condition, yet there is still not a standard treatment. Thus, other approaches are needed to positively impact brain health and reduce the long-term risk of memory loss, cognitive decline, or AD. Changes in how blood flow in the brain is controlled may explain some of the cognitive complaints associated with GWI. Currently, the long-term effects of GWI on brain blood flow control, and how this may change as a person ages, is poorly understood. This makes it difficult to differentiate normal changes associated with aging from changes in the brain that are caused by GWI. Understanding how brain blood flow is controlled in Veterans with GWI, especially during the middle-aged years is important because this is the time where we can intervene with lifestyle or drug therapy to lower future risk of AD. Another common symptom in GWI is autonomic nervous system dysfunction. Research studies in Veterans have demonstrated that Veterans with GWI demonstrate altered heart rate and blood pressure in response to acute stress. Our preliminary data suggests that autonomic dysfunction is a potential factor that is altered by aging and separates healthy adults with normal brain blood flow regulation from adults with abnormal (i.e., reduced) brain blood flow regulation. Importantly, the link between the autonomic nervous system and the regulation of brain blood flow may also be relevant to Veterans with GWI. It is possible that autonomic dysfunction in Veterans with GWI is associated with abnormal brain blood flow regulation. Our hypothesis is that Veterans with GWI demonstrate abnormal brain blood flow regulation and autonomic dysfunction when compared with deployment-matched Veterans. Our second hypothesis is that brain blood flow and autonomic nervous system variables will be associated with other markers of brain aging that are relevant to cognitive decline. We will combine established and new techniques to evaluate differences in the blood vessels of the brain of Veterans with GWI because we think these will be important to target in future interventions. Importantly, there are already interventions that have been shown to improve blood vessel function in other areas of the body, so it is possible that in the future these could be applied to Veterans with GWI. This proposal will use state-of-the-art techniques to deepen our understanding of how brain blood flow regulation is affected by autonomic dysfunction in Veterans with GWI. Then we will determine how these variables relate to future AD risk. Collectively, this project will offer insight into brain health in GWI. The proposed project will allow the Applicant, who is an Early-Career Investigator, to acquire the skills and gain the experience in studying GWI. This will allow the Applicant to apply new ideas to identify potential biomarkers and develop novel interventions to help prevent cognitive decline and AD in Veterans with GWI.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 16, 2019
- Source ID
- W81XWH1910381
Entities
People
- Jill N. Barnes
Organizations
- United States Army
- University of Wisconsin–Madison