Date:  Feb. 13, 2014


U.S. Military Personnel Exposed to Blasts at Greater Risk for PTSD, Brain Injury, and Other Long-Term Health Outcomes Not Associated With Immediate Injuries

WASHINGTON – U.S. soldiers exposed to blasts while deployed in Iraq and Afghanistan have an increased risk of developing adverse health outcomes over the long term, such as post-traumatic stress disorder (PTSD) and, in certain cases of traumatic brain injury (TBI), growth hormone deficiency, and persistent post-concussive symptoms including headaches, says a new report by the Institute of Medicine.  The committee that wrote the report focused on health consequences experienced at least six months after a blast.

Tens of thousands of U.S. soldiers serving in Iraq and Afghanistan have been killed or wounded by explosions during those wars.  Blasts are the leading cause of death and injury on the battlefield, accounting for about 75 percent of all combat-related injuries in U.S. military personnel.  Several major patterns of injury result from explosions, from injuries caused by the blast wave itself to those caused by fragments of debris propelled by the explosion, to subsequent illnesses from, for example, chemical substances released by a bomb.  When the energy from the blast shock wave is absorbed in the human body, it disrupts the natural state of the body at a basic or even molecular level, which can cause tissue damage not immediately apparent after the blast.

“Acute physical and psychological health outcomes in people who survive blast explosions can be devastating, but the long-term consequences are less clear, particularly for individuals who show no external signs of injury from exposure to blast waves or may not even be aware that they were exposed,” said Stephen L. Hauser, chair of the committee that wrote the report, Robert A. Fishman Distinguished Professor, and chair of the department of neurology of the University of California, San Francisco. 

Some evidence suggests that blast exposure can result in long-term hearing damage and muscle or bone impairment such as osteoarthritis.  However, the data on these outcomes were not strong enough to draw a direct cause-and-effect relationship.  Though an association could exist, evidence was more tentative to link blast exposure to long-term effects on cardiovascular and pulmonary function, substance-abuse disorders, and chronic pain in the absence of a severe, immediate injury.  While there is substantial overlap between symptoms of mild TBI and PTSD, limited evidence suggests that most of the shared symptoms could be a result of PTSD and not a direct result of TBI alone.

The committee outlined several recommendations for urgent research to inform decisions on how to prevent and better diagnose blast injuries, and how to treat, rehabilitate, and support victims of battlefield trauma in the immediate aftermath and in the long term.  In this research agenda, it is especially important to emphasize that blasts create unusual patterns of injury that can affect multiple organs and systems of the body, a complexity that has often been overlooked in previous studies.  Understanding these cross-system interactions should be a priority for future research, the committee stressed.  It also is essential that future studies use a standardized definition of blast exposure, once it is developed. 

For health outcomes associated with blast exposure, the U.S. Department of Veteran Affairs should evaluate the approaches already in place to detect, treat, and rehabilitate blast injuries, the report says.  Because injuries from blast may go undetected for long periods, the VA should conduct epidemiologic and mechanistic studies to identify biomarkers of blast injury through advanced imaging and molecular methods that could serve as surrogates of exposure.

The majority of past studies have used self-reported exposure data, rather than objective measures.  Therefore, the committee recommended DOD develop and deploy data collection technologies that quantitatively measure components of blast and characteristics of the exposure environment in real-time and also link these data with self-reported exposure histories and demographic, medical, and operational information.

The Institute of Medicine study was sponsored by the U.S. Department of Veteran Affairs.  This is the ninth volume of its congressionally mandated series on health effects related to military service during wartime, which began in 1998 in response to the growing concerns of ill Gulf War veterans.  Established in 1970 under the charter of the National Academy of Sciences, the Institute of Medicine provides independent, objective, evidence-based, peer-reviewed advice to policymakers, health professionals, the private sector, and the public.  The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies.   A committee roster follows.


Jennifer Walsh, Senior Media Officer
Chelsea Dickson, Media Associate
Office of News and Public Information
202-334-2138; e-mail
Twitter: @NAS_news and @NASciences
RSS feed:

Copies of Gulf War and Health, Volume 9: Long-Term Effects of Blast Exposures are available from the National Academies Press at or by calling tel. 202-334-3313 or 1-800-624-6242.  Reporters may obtain a copy from the Office of News and Public Information (contacts listed above).


Committee on Gulf War and Health: Long-Term Effects of Blast Exposure

Stephen L. Hauser, M.D. (chair)
Professor and Chair
Department of Neurology
University of California
San Francisco

Jeffrey J. Bazarian, M.D., M.P.H.
Associate Professor
Departments of Emergency Medicine, Neurology, Neurosurgery, and Community and Preventive Medicine
School of Medicine and Dentistry
University of Rochester
Rochester, N.Y.

Ibolja Cernak, Ph.D., M.D.
Canadian Military and Veterans’ Clinical Rehabilitation
Faculty of Rehabilitation Medicine
University of Alberta

Lin Chang, M.D.
Division of Digestive Diseases, and
Center for Neurobiology of Stress
David Geffen School of Medicine
University of California
Los Angeles

Kimberly P. Cockerham, M.D.
Adjunct Clinical Associate Professor
Department of Ophthalmology
School of Medicine
Stanford University
Stanford, Calif.

Karen J. Cruickshanks, Ph.D.
Departments of Ophthalmology and Visual Sciences and Population Health Sciences
School of Medicine and Public Health
University of Wisconsin

Francesca Dominici, Ph.D.
Department of Biostatistics
School of Public Health
Harvard University

Judy R. Dubno, Ph.D.
Department of Otolaryngology
Medical University of South Carolina

Theodore J. Iwashyna, Ph.D., M.D.
Associate Professor of Internal Medicine
Division of Pulmonary and Critical Care Medicine
University of Michigan Health System
Ann Arbor

S. Claiborne Johnston, Ph.D., M.D.
Associate Vice Chancellor of Research,
Director of Clinical and Translational Science Institute, and
Professor of Neurology and Epidemiology
University of California
San Francisco

S. Andrew Josephson, M.D.
Associate Professor of Clinical Neurology, and
UCSF Neurohospitalist Program
University of California
San Francisco

Kenneth W. Kizer, M.D., M.P.H.
Distinguished Professor
School of Medicine and Betty Irene Moore School of Nursing, and
Institute for Population Health Improvement
University of California Davis Health System

William C. Mann, Ph.D.
Distinguished Professor and Chair
Department of Occupational Therapy, and
Florida Institute on Disability and Rehabilitation
College of Public Health and Health Professions
University of Florida

Linda J. Noble-Haeusslein, Ph.D.
Professor and Alvera L. Kan Endowed Chair
Departments of Neurological Surgery and Physical Therapy and Rehabilitation Science
University of California
San Francisco

Edmond L. Paquette, M.D.
Assistant Professor of Surgery
Virginia Commonwealth University School of Medicine, Inova Fairfax Campus; and
Dominion Urological Consultants
Fairfax, Va.

Alan L. Peterson, Ph.D.
Professor and Chief
Division of Behavioral Medicine
Department of Psychiatry
University of Texas Health Science Center
San Antonio

Karol E. Watson, M.D., Ph.D.
Associate Professor of Medicine and Co-Director
UCLA Program in Preventive Cardiology
David Geffen School of Medicine
University of California
Los Angeles


Abigail Mitchell
Study Director