Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans
The long-term effects of blast exposure are a major health concern for combat veterans returning from the recent conflicts in Iraq and Afghanistan. We used an optimized diffusion tensor imaging tractography algorithm to assess white matter (WM) fractional anisotropy (FA) in blast-exposed Iraq and Af...
Main Authors: | , , , , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Frontiers Media S.A.
2017-04-01
|
Series: | Frontiers in Neurology |
Subjects: | |
Online Access: | http://journal.frontiersin.org/article/10.3389/fneur.2017.00127/full |
id |
doaj-9fe9e595471d41ca8cb0b0335987c620 |
---|---|
record_format |
Article |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Iliyan Ivanov Corey Fernandez Corey Fernandez Effie M. Mitsis Effie M. Mitsis Dara L. Dickstein Dara L. Dickstein Edmund Wong Cheuk Y. Tang Jessie Simantov Jessie Simantov Charlene Bang Charlene Bang Erin Moshier Mary Sano Mary Sano Gregory A. Elder Gregory A. Elder Gregory A. Elder |
spellingShingle |
Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Iliyan Ivanov Corey Fernandez Corey Fernandez Effie M. Mitsis Effie M. Mitsis Dara L. Dickstein Dara L. Dickstein Edmund Wong Cheuk Y. Tang Jessie Simantov Jessie Simantov Charlene Bang Charlene Bang Erin Moshier Mary Sano Mary Sano Gregory A. Elder Gregory A. Elder Gregory A. Elder Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans Frontiers in Neurology adult brain injury diffusion tensor imaging magnetic resonance imaging cognitive function military injury |
author_facet |
Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Erin A. Hazlett Iliyan Ivanov Corey Fernandez Corey Fernandez Effie M. Mitsis Effie M. Mitsis Dara L. Dickstein Dara L. Dickstein Edmund Wong Cheuk Y. Tang Jessie Simantov Jessie Simantov Charlene Bang Charlene Bang Erin Moshier Mary Sano Mary Sano Gregory A. Elder Gregory A. Elder Gregory A. Elder |
author_sort |
Erin A. Hazlett |
title |
Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans |
title_short |
Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans |
title_full |
Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans |
title_fullStr |
Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans |
title_full_unstemmed |
Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat Veterans |
title_sort |
blast exposure, white matter integrity, and cognitive function in iraq and afghanistan combat veterans |
publisher |
Frontiers Media S.A. |
series |
Frontiers in Neurology |
issn |
1664-2295 |
publishDate |
2017-04-01 |
description |
The long-term effects of blast exposure are a major health concern for combat veterans returning from the recent conflicts in Iraq and Afghanistan. We used an optimized diffusion tensor imaging tractography algorithm to assess white matter (WM) fractional anisotropy (FA) in blast-exposed Iraq and Afghanistan veterans (n = 40) scanned on average 3.7 years after deployment/trauma exposure. Veterans diagnosed with a blast-related mild traumatic brain injury (mTBI) were compared to combat veterans with blast exposure but no TBI diagnosis. Blast exposure was associated with decreased FA in several WM tracts. However, total blast exposure did not correlate well with neuropsychological testing performance and there were no differences in FA based on mTBI diagnosis. Yet, veterans with mTBI performed worse on every neurocognitive test administered. Multiple linear regression across all blast-exposed veterans using a six-factor prediction model indicated that the amount of blast exposure accounted for 11–15% of the variability in composite FA scores such that as blast exposure increased, FA decreased. Education accounted for 10% of the variability in composite FA scores and 25–32% of FA variability in the right cingulum, such that as level of education increased, FA increased. Total blast exposure, age, and education were significant predictors of FA in the left cingulum. We did not find any effect of post-traumatic stress disorder on cognition or composite FA. In summary, our findings suggest that greater total blast exposure is a contributing factor to poor WM integrity. While FA was not associated with neurocognitive performance, we hypothesize that FA changes in the cingulum in veterans with multiple combat exposures and no head trauma prior to deployment may represent a marker of vulnerability for future deficits. Future work needs to examine this longitudinally. |
topic |
adult brain injury diffusion tensor imaging magnetic resonance imaging cognitive function military injury |
url |
http://journal.frontiersin.org/article/10.3389/fneur.2017.00127/full |
work_keys_str_mv |
AT erinahazlett blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT erinahazlett blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT erinahazlett blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT erinahazlett blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT iliyanivanov blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT coreyfernandez blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT coreyfernandez blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT effiemmitsis blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT effiemmitsis blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT daraldickstein blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT daraldickstein blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT edmundwong blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT cheukytang blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT jessiesimantov blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT jessiesimantov blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT charlenebang blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT charlenebang blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT erinmoshier blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT marysano blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT marysano blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT gregoryaelder blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT gregoryaelder blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans AT gregoryaelder blastexposurewhitematterintegrityandcognitivefunctioniniraqandafghanistancombatveterans |
_version_ |
1725693667565371392 |
spelling |
doaj-9fe9e595471d41ca8cb0b0335987c6202020-11-24T22:43:57ZengFrontiers Media S.A.Frontiers in Neurology1664-22952017-04-01810.3389/fneur.2017.00127237381Blast Exposure, White Matter Integrity, and Cognitive Function in Iraq and Afghanistan Combat VeteransErin A. Hazlett0Erin A. Hazlett1Erin A. Hazlett2Erin A. Hazlett3Iliyan Ivanov4Corey Fernandez5Corey Fernandez6Effie M. Mitsis7Effie M. Mitsis8Dara L. Dickstein9Dara L. Dickstein10Edmund Wong11Cheuk Y. Tang12Jessie Simantov13Jessie Simantov14Charlene Bang15Charlene Bang16Erin Moshier17Mary Sano18Mary Sano19Gregory A. Elder20Gregory A. Elder21Gregory A. Elder22Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USAResearch & Development, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USAFishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA1Mental Illness Research, Education, and Clinical Center (MIRECC VISN 2 South), James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USAResearch & Development, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USARehabilitation Medicine Service, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Pathology, Uniformed Service University of Health Science, Bethesda, MD, USAFishberg Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USADepartment of Radiology, Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, New York, NY, USADepartment of Radiology, Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, New York, NY, USARehabilitation Medicine Service, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USARehabilitation Medicine Service, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USAResearch & Development, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USADepartment of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USADepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA0Neurology Service, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USAThe long-term effects of blast exposure are a major health concern for combat veterans returning from the recent conflicts in Iraq and Afghanistan. We used an optimized diffusion tensor imaging tractography algorithm to assess white matter (WM) fractional anisotropy (FA) in blast-exposed Iraq and Afghanistan veterans (n = 40) scanned on average 3.7 years after deployment/trauma exposure. Veterans diagnosed with a blast-related mild traumatic brain injury (mTBI) were compared to combat veterans with blast exposure but no TBI diagnosis. Blast exposure was associated with decreased FA in several WM tracts. However, total blast exposure did not correlate well with neuropsychological testing performance and there were no differences in FA based on mTBI diagnosis. Yet, veterans with mTBI performed worse on every neurocognitive test administered. Multiple linear regression across all blast-exposed veterans using a six-factor prediction model indicated that the amount of blast exposure accounted for 11–15% of the variability in composite FA scores such that as blast exposure increased, FA decreased. Education accounted for 10% of the variability in composite FA scores and 25–32% of FA variability in the right cingulum, such that as level of education increased, FA increased. Total blast exposure, age, and education were significant predictors of FA in the left cingulum. We did not find any effect of post-traumatic stress disorder on cognition or composite FA. In summary, our findings suggest that greater total blast exposure is a contributing factor to poor WM integrity. While FA was not associated with neurocognitive performance, we hypothesize that FA changes in the cingulum in veterans with multiple combat exposures and no head trauma prior to deployment may represent a marker of vulnerability for future deficits. Future work needs to examine this longitudinally.http://journal.frontiersin.org/article/10.3389/fneur.2017.00127/fulladult brain injurydiffusion tensor imagingmagnetic resonance imagingcognitive functionmilitary injury |