Citation: Rayhan RU, Stevens BW, Timbol CR, Adewuyi O, Walitt B, et al. (2013) Increased Brain White Matter Axial Diffusivity Associated with Fatigue, Pain and Hyperalgesia in Gulf War Illness. PLoS ONE 8(3): e58493. doi:10.1371/journal.pone.0058493
Abstract
Background
Gulf War exposures in 1990 and 1991 have caused 25% to 30% of deployed personnel to develop a syndrome of chronic fatigue, pain, hyperalgesia, cognitive and affective dysfunction.
Methods
Gulf War veterans (n = 31) and sedentary veteran and civilian controls (n = 20) completed fMRI scans for diffusion tensor imaging. A combination of dolorimetry, subjective reports of pain and fatigue were correlated to white matter diffusivity properties to identify tracts associated with symptom constructs.
Results
Gulf War Illness subjects had significantly correlated fatigue, pain, hyperalgesia, and increased axial diffusivity in the right inferior fronto-occipital fasciculus. ROC generated thresholds and subsequent binary regression analysis predicted CMI classification based upon axial diffusivity in the right inferior fronto-occipital fasciculus. These correlates were absent for controls in dichotomous regression analysis.
Conclusion
The right inferior fronto-occipital fasciculus may be a potential biomarker for Gulf War Illness. This tract links cortical regions involved in fatigue, pain, emotional and reward processing, and the right ventral attention network in cognition. The axonal neuropathological mechanism(s) explaining increased axial diffusivity may account for the most prominent symptoms of Gulf War Illness.
Citation: Rayhan RU, Stevens BW, Timbol CR, Adewuyi O, Walitt B, et al. (2013) Increased Brain White Matter Axial Diffusivity Associated with Fatigue, Pain and Hyperalgesia in Gulf War Illness. PLoS ONE 8(3): e58493. doi:10.1371/journal.pone.0058493
Editor: Yu-Feng Zang, Hangzhou Normal University, China
Received: December 12, 2012; Accepted: February 7, 2013; Published: March 20, 2013
Copyright: ? 2013 Rayhan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: Sources of funding were provided by the Department of Defense Congressionally Directed Medical Research Program (CDMRP) award W81-XWH-09-1-0526. Research support for the Clinical Research Unit at Georgetown University Medical Center was funded in whole or in part with federal funds (Grant # UL1TR000101, previously UL1RR031975) from the National Center for Advancing Translational Sciences (NCATS), National Institutes of Health (NIH), through the Clinical and Translational Science Awards Program (CTSA), a trademark of DHHS, part of the Roadmap Initiative, ?Re-Engineering the Clinical Research Enterprise.? The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
