Assessment of MRI-Based Marker of Dopaminergic Integrity as a Biological Indicator of Gulf War Illness
Abstract
Approximately one third of the nearly 700,000 U.S. military veterans who served in the 1990-1991 Persian Gulf War continue to suffer from Gulf War illness (GWI), a complex of chronic symptoms that includes persistent headaches, memory and cognitive difficulties, widespread pain, unexplained fatigue, gastrointestinal problems, and other difficulties. Multiple findings of significant central nervous system (CNS) involvement have been reported in veterans with GWI, including preliminary findings suggestive of alterations in central dopamine levels and signaling. The current study leveraged existing MRI brain imaging data from a well-characterized sample of 139 Gulf War veterans that included 120 GWI cases (defined by Kansas criteria) and 19 veteran controls. Using high resolution diffusion tensor imaging (DTI), the study provided in-depth assessment of white matter integrity in the substantianigra (SN), the primary source of central dopamine production, and six thalamic nuclei. Analysis of white matter integrity in regions of interest were based on fractional anisotropy (FA) measures using methods previously developed and validated by study investigators. Results indicate that GWI is associated with significant depletion of white matter integrity affecting the SN, as indicated by significantly reduced mean FA in cases vs. controls (p less than 0.0001), but only minimal changes in thalamic nuclei. Observed SN FA reductions were significantly correlated with greater GWI severity overall and with severity of several symptom domains. Lower SN FA was also significantly associated with two deployment experiences/exposures during the Gulf War, use of skin pesticides and having one or more mild traumatic brain injuries in theater. The observed SN changes would be expected to result in substantial reduction of central dopamine levels and neurotransmission.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2021
- Accession Number
- AD1169480
Entities
People
- Lea Steele
Organizations
- Baylor College of Medicine