VOLUME 7
Long-Term Consequences of Traumatic Brain Injury
THE NATIONAL ACADEMIES PRESS
Washington, D.C.
www.nap.edu
Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page R1
Committee on Gulf War and Health: Brain Injury in Veterans and
Long-Term Health Outcomes
Board on Population Health and Public Health Practice
OCR for page R1
THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National
Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National
Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report
were chosen for their special competences and with regard for appropriate balance.
This study was supported by Contract V101(93) P-2136, Task Order 8 between the National Academy of Sciences
and Department of Veterans Affairs. Any opinions, findings, conclusions, or recommendations expressed in this
publication are those of the authors and do not necessarily reflect the view of the organizations or agencies that
provided support for this project.
International Standard Book Number-13: 978-0-309-12408-9
International Standard Book Number-10: 0-309-12408-5
Additional copies of this report are available from the National Academies Press, 500 Fifth Street, N.W., Lockbox
285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet,
http://www.nap.edu.
For more information about the Institute of Medicine, visit the IOM home page at www.iom.edu.
Copyright 2009 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
The serpent has been a symbol of long life, healing, and knowledge among almost all cultures and religions since the
beginning of recorded history. The serpent adopted as a logotype by the Institute of Medicine is a relief carving from
ancient Greece, now held by the Staatliche Museen in Berlin.
Suggested citation: IOM (Institute of Medicine). 2009. Gulf War and Health, Volume 7: Long-term Consequences of
Traumatic Brain Injury. Washington, DC: The National Academies Press.
OCR for page R1
OCR for page R1
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars
engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their
use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has
a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone
is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of
Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the
selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal
government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national
needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M.
Vest is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of
eminent members of appropriate professions in the examination of policy matters pertaining to the health of the
public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional
charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care,
research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad
community of science and technology with the Academy’s purposes of furthering knowledge and advising the
federal government. Functioning in accordance with general policies determined by the Academy, the Council has
become the principal operating agency of both the National Academy of Sciences and the National Academy of
Engineering in providing services to the government, the public, and the scientific and engineering communities.
The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr.
Charles M. Vest are chair and vice chair, respectively, of the National Research Council.
www.national-academies.org
.
iv
OCR for page R1
COMMITTEE ON GULF WAR AND HEALTH: BRAIN INJURY IN
VETERANS AND LONG-TERM HEALTH OUTCOMES
GEORGE W. RUTHERFORD, MD (Chair) Salvatore Pablo Lucia Professor and Vice Chair,
Department of Epidemiology and Biostatistics; Director, Prevention and Public Health
Group, Global Health Sciences, University of California, San Francisco School of
Medicine
JEFFREY J. BAZARIAN, MD, MPH, Associate Professor, Departments of Emergency
Medicine and Neurology, University of Rochester School of Medicine and Dentistry
IBOLJA CERNAK, PhD, MD, Medical Director, Johns Hopkins University, Applied Physics
Laboratory
JOHN D. CORRIGAN, PhD, Professor, Department of Physical Medicine and Rehabilitation,
Ohio State University
SUREYYA S. DIKMEN, PhD, Professor, Department of Rehabilitation Medicine and Adjunct
Professor of Neurological Surgery and Psychiatry and Behavioral Sciences, University of
Washington
M. SEAN GRADY, MD, Chairman, Department of Neurosurgery, University of Pennsylvania
School of Medicine
DALE C. HESDORFFER, PhD, MPH, Associate Professor of Clinical Epidemiology,
Gertrude H. Sergievsky Center, Columbia University
JESS F. KRAUS, PhD, MPH, Director, Southern California Injury Prevention Research Center,
Professor of Epidemiology, University of California, Los Angeles, School of Public
Health
HARVEY S. LEVIN, PhD, Professor, Director of Research, Cognitive Neuroscience
Laboratory, Department of Physical Medicine and Rehabilitation, Baylor College of
Medicine
LINDA NOBLE, PhD, Professor, Department of Neurological Surgery and Department of
Physical Therapy and Rehabilitation Science, University of California, San Francisco
SAMUEL J. POTOLICCHIO, MD, Professor, Department of Neurology, George Washington
University Medical Center
SCOTT L. RAUCH, MD, Chair, Partners Psychiatry and Mental Health; President and
Psychiatrist in Chief, McLean Hospital; Professor of Psychiatry, Harvard Medical School
WILLIAM STIERS, PhD, ABPP, Assistant Professor, Department of Physical Medicine and
Rehabilitation, Johns Hopkins University
CAROL A. TAMMINGA, MD, Professor, Department of Psychiatry, University of Texas
Southwestern Medical Center at Dallas
NANCY TEMKIN, PhD, Professor, Departments of Neurological Surgery and Biostatistics,
University of Washington
MARC G. WEISSKOPF, PhD, ScD, Mark and Catherine Winkler Assistant Professor,
Departments of Environmental Health and Epidemiology, Harvard School of Public
Health
v
OCR for page R1
STAFF
CAROLYN FULCO, Senior Program Officer
ABIGAIL MITCHELL, Senior Program Officer
ROBERTA WEDGE, Senior Program Officer
NAOKO ISHIBE, Program Officer
JENNIFER SAUNDERS, Senior Program Associate
DEEPALI PATEL, Senior Program Associate (until October 2007)
RENEE WLODARCZYK, Senior Program Associate
JOE GOODMAN, Senior Program Assistant
NORMAN GROSSBLATT, Senior Editor
CHRISTIE BELL, Financial Officer
HOPE HARE, Administrative Assistant
ROSE MARIE MARTINEZ, Director, Board on Population Health and Public Health Practice
CONSULTANTS
MIRIAM DAVIS, Independent Medical Writer, Silver Spring, MD
JOAN MACHAMER, Independent Consultant, University of Washington, Seattle, WA
vi
OCR for page R1
REVIEWERS
This report has been reviewed in draft form by persons chosen for their diverse
perspectives and technical expertise, in accordance with procedures approved by the National
Research Council’s Report Review Committee. The purpose of this independent review is to
provide candid and critical comments that will assist the institution in making its published
report as sound as possible and to ensure that the report meets institutional standards of
objectivity, evidence, and responsiveness to the study charge. The review comments and draft
manuscript remain confidential to protect the integrity of the deliberative process. We thank the
following for their review of this report:
Dan G. Blazer, Duke University Medical Center
Linda Cowan, Department of Biostatistics and Epidemiology, University of Oklahoma Health
Sciences Center
Ramon Diaz-Arrastia, Department of Neurology, University of Texas Southwestern Medical
School
Sandro Galea, Center for Social Epidemiology and Population Health, University of Michigan
Tessa Hart, Moss Rehabilitation Research Institute, Albert Einstein Healthcare Network
Janice L. Krupnick, Department of Psychiatry, Trauma and Loss Program, Georgetown
University Medical Center
James L. Levenson, Department of Psychiatry, Virginia Commonwealth School of Medicine
Kathryn Saatman, Spinal Cord and Brain Injury Research Center, University of Kentucky
Chandler Medical Center
Murray B. Stein, Department of Psychiatry, University of California, San Diego
Although the reviewers listed above have provided many constructive comments and
suggestions, they were not asked to endorse the conclusions or recommendations, nor did they
see the final draft of the report before its release. The review of this report was overseen by Dr.
Johanna T. Dwyer, Tufts University School of Medicine and Friedman School of Nutrition
Science and Policy, Frances Stern Nutrition Center, Tufts-New England Medical Center and Dr.
Robert S. Lawrence, Center for a Livable Future, Johns Hopkins Bloomberg School of Public
Health. Appointed by the National Research Council and the Institute of Medicine, they were
responsible for making certain that an independent examination of the report was carried out in
accordance with institutional procedures and that all review comments were carefully
considered. Responsibility for the final content of the report rests entirely with the author
committee and the institution.
vii
OCR for page R1
viii
OCR for page R1
CONTENTS
PREFACE .................................................................................................................................... xiii
SUMMARY.....................................................................................................................................1
1 INTRODUCTION ....................................................................................................................13
Background ...............................................................................................................................13
Traumatic Brain Injury..............................................................................................................14
Operation Enduring Freedom and Operation Iraqi Freedom ....................................................15
Charge to the Committee ..........................................................................................................15
Scope of the Report...................................................................................................................15
Organization of the Report........................................................................................................16
References .................................................................................................................................17
2 BIOLOGY OF TRAUMATIC BRAIN INJURY .....................................................................19
Pathobiology of Traumatic Brain Injury ...................................................................................19
Traditional Classifications of Traumatic Brain Injury ..............................................................25
Classification According to Extent of Pathology......................................................................25
Classification According to Biomechanics of Injury ................................................................27
Therapeutics and Traumatic Brain Injury .................................................................................28
Summary of Pathobiology of Traumatic Brain Injury ..............................................................29
Traumatic Brain Injuries Relevant to the Military....................................................................30
Basic Mechanisms of Explosive Injuries ..................................................................................31
Severity Scoring of Blast Injuries and Traumatic Brain Injury ................................................41
References .................................................................................................................................46
3 EPIDEMIOLOGY OF ADULT TRAUMATIC BRAIN INJURY ..........................................59
Incidence of Traumatic Brain Injury.........................................................................................61
Brain Injury Severity.................................................................................................................63
Risk Factors for Traumatic Brain Injury...................................................................................64
Recurrent Traumatic Brain Injury.............................................................................................67
Traumatic Brain Injury and Short-Term Outcomes ..................................................................68
Summary ...................................................................................................................................69
References .................................................................................................................................96
4 CONSIDERATIONS IN IDENTIFYING AND EVALUATING THE LITERATURE .......103
Identification of the Literature ................................................................................................103
Types of Evidence...................................................................................................................104
Inclusion Criteria.....................................................................................................................110
Considerations in Assessing the Strength of Evidence ...........................................................112
Limitations of Studies .............................................................................................................113
References ...............................................................................................................................115
ix
OCR for page R1
5 MAJOR COHORT STUDIES ................................................................................................117
General Limitations of Cohort Studies ...................................................................................117
Organization of the Chapter ....................................................................................................118
Military Studies.......................................................................................................................118
Population-Based Studies .......................................................................................................127
Other Cohort Studies...............................................................................................................133
Studies of Sports-Related Traumatic Brain Injury..................................................................140
References ...............................................................................................................................166
6 NEUROCOGNITIVE OUTCOMES ......................................................................................173
Penetrating Brain Injury..........................................................................................................173
Closed Head Injury .................................................................................................................181
References ...............................................................................................................................194
7 NEUROLOGIC OUTCOMES................................................................................................197
Seizure Disorders ....................................................................................................................197
Postconcussion Symptoms ......................................................................................................210
Ocular and Visual Motor Deterioration ..................................................................................224
Endocrine Disorders................................................................................................................227
Neurodegenerative Diseases ...................................................................................................237
Dementia of the Alzheimer Type............................................................................................237
Dementia Pugilistica ...............................................................................................................243
Parkinsonism ...........................................................................................................................246
Multiple Sclerosis ...................................................................................................................251
Amyotrophic Lateral Sclerosis................................................................................................254
References ...............................................................................................................................256
8 PSYCHIATRIC OUTCOMES ...............................................................................................265
Mood Disorders.......................................................................................................................266
Suicide.....................................................................................................................................276
Anxiety Disorders ...................................................................................................................281
Other Psychiatric Outcomes....................................................................................................289
Aggressive Behaviors.........................................................................................................289
Drug and Alcohol Abuse Disorders ...................................................................................291
Psychotic Disorders............................................................................................................292
References ...............................................................................................................................297
9 SOCIAL FUNCTIONING ......................................................................................................301
Primary Studies of Military Populations.................................................................................301
Primary Studies of Civilian Populations .................................................................................303
Secondary Studies ...................................................................................................................307
Summary and Conclusions......................................................................................................314
References ...............................................................................................................................328
10 OTHER HEALTH OUTCOMES ...........................................................................................333
Mortality and Traumatic Brain Injury.....................................................................................333
x
OCR for page R1
Primary Studies .......................................................................................................................333
Secondary Studies ...................................................................................................................336
Summary and Conclusions......................................................................................................339
Brain Tumors and Traumatic Brain Injury .............................................................................350
Primary Studies .......................................................................................................................350
Secondary Studies ...................................................................................................................354
Summary and Conclusions......................................................................................................355
References ...............................................................................................................................364
11 CONCLUSIONS AND RECOMMENDATIONS .................................................................367
Quality of the Studies..............................................................................................................367
Overview of Health Outcomes................................................................................................368
Recommendations ...................................................................................................................370
INDEX .........................................................................................................................................373
TABLES AND FIGURES
TABLE 2.1 Safety Recommendations for Standoff Distances from
Different Types of Exploding Bombs....................................................................................31
TABLE 2.2 Overpressure Effects on Surrounding Materials and Unprotected Persons...............33
TABLE 2.3 Summary of Most Important Body-System Injuries Induced by Concomitant
Primary, Secondary, Tertiary, and Quaternary Effects of Blast ............................................34
TABLE 3.1 Glasgow Coma Scales and Glasgow Outcome Scales...............................................70
TABLE 3.2 US TBI Incidence Studies: Case Identification, Data Source, and TBI Severity
Scoring ...................................................................................................................................71
TABLE 3.3 Non-US Incidence Studies: Case Identification, Data Source,
and TBI Severity Score..........................................................................................................75
TABLE 3.4 US TBI Incidence Studies..........................................................................................79
TABLE 3.5 Non-US TBI Incidence Data......................................................................................81
TABLE 3.6 US TBI Deaths and Mortality Rates ..........................................................................84
TABLE 3.7 Non-US TBI Deaths and Mortality Rates ..................................................................85
TABLE 3.8 Percent Severity Distributions of Hospitalized Patients
in US and Non-US Incidence Studies....................................................................................87
TABLE 3.9 Highest Age-Specific TBI Rates and Gender Rate Ratios: US Studies.....................89
TABLE 3.10 Highest Age-Specific TBI Rates and Gender Rate Ratios: Non-US Studies ..........90
TABLE 3.11 Percent Distributions of TBI Incidence Cases by External Cause: US Studies.......91
TABLE 3.12 Percent Distributions of TBI Incidence Cases by External Cause:
Non-US Studies .....................................................................................................................92
TABLE 3.13 TBI In-Hospital Case Fatality Rates (CFR) from US Population-Based Studies....93
TABLE 3.14 TBI In-Hospital Case Fatality Rates (CFR) from Non-US
Population-Based Studies ......................................................................................................94
TABLE 3.15 Percent Distribution of GOS Outcome Categories at Hospital Discharge
Rate for US and Non-US Studies...........................................................................................95
TABLE 5.1 Major Cohort Studies (Shaded) and Derivative Studies ..........................................143
TABLE 6.1 Penetrating Head Injury and Neurocognitive Outcomes .........................................178
TABLE 6.2 Closed Head Injury and Neurocognitive Outcomes ................................................189
TABLE 7.1 Seizure Disorders and TBI.......................................................................................204
xi
OCR for page R1
TABLE 7.2 Symptoms After Deployment According to Type of Injury During
Deployment..........................................................................................................................211
TABLE 7.3 Frequency of Symptoms on RPCS Questionnaire ...................................................214
TABLE 7.4 Prevalence of Subjective Complaints 5 Years After Injury.....................................216
TABLE 7.5 Postconcussive Symptoms and TBI.........................................................................219
TABLE 7.6 Ocular and Visual Motor Deterioration and TBI .....................................................226
TABLE 7.7 Endocrine Disorders and TBI ..................................................................................233
TABLE 7.8 Dementia of the Alzheimer Type and TBI...............................................................242
TABLE 7.9 Parkinsonism and TBI..............................................................................................249
TABLE 7.10 Multiple Sclerosis and TBI ....................................................................................253
TABLE 8.1 Psychologic Outcomes—Mood-Disorder Studies ...................................................270
TABLE 8.2 Psychologic Outcomes—TBI and Suicide...............................................................279
TABLE 8.3 Psychologic Outcomes—Anxiety Disorder Studies ................................................285
TABLE 8.4 Psychologic Outcomes—Personality Disorder Studies ...........................................294
TABLE 9.1 Social Function ........................................................................................................316
TABLE 10.1 TBI and Mortality ..................................................................................................340
TABLE 10.2 TBI and Brain Tumors ...........................................................................................356
FIGURE 2.1 Pathologic classification of TBI ...............................................................................26
FIGURE 2.2 Classification of TBI based on primary insult..........................................................28
FIGURE 2.3 Potential consequences of blast exposure.................................................................30
FIGURE 2.4 Explosion-induced shock waves...............................................................................32
FIGURE 2.5 Examination and diagnosis algorithm for blast injuries ...........................................36
FIGURE 2.6 Complex mechanisms of blast-induced neurotrauma...............................................37
FIGURE 2.7 Brief Traumatic Brain Injury Screen........................................................................45
xii
OCR for page R1
PREFACE
The Institute of Medicine (IOM) has a long-standing role of providing assistance to the
Department of Veterans Affairs (VA) with regard to veterans’ health. The current series of
studies on Gulf War and Health, of which this study is one, began in 1998 when Congress passed
two laws on Gulf War veterans’ health in response to the recognition that many Gulf War
veterans returning from the 1991 Persian Gulf War were suffering from a multisymptom illness
of poorly understood pathogenesis that proved difficult to diagnose and treat.
The United States is once again engaged in a military conflict in the Middle East. The
conflicts in Afghanistan (Operation Enduring Freedom [OEF]) and in Iraq (Operation Iraqi
Freedom [OIF]) have been characterized by a type of combat different from that seen in the 1991
war, in that there have been many more deaths, polytrauma, and traumatic brain injury (TBI).
The VA, under authorization granted in the 1998 legislation, has asked IOM to determine long-
term health outcomes associated with TBI. TBI has been called the signature injury of OEF and
OIF primarily due to blast exposure that is characteristic of this conflict. Exposure to blast might
cause instant death, injuries with immediate manifestation of symptoms, or injuries with delayed
manifestation. Blast-induced neurotrauma, however, has not been studied sufficiently to confirm
reports of long-term effects.
That many returning veterans have TBI will likely mean long-term challenges for them
and their family members. Veterans will need support systems at home and in their communities
to assist them in coping with the long-term sequelae of their injuries. Further, many veterans will
have undiagnosed brain injury because not all TBIs have immediately recognized effects or are
easily diagnosed with neuroimaging techniques.
In an effort to detail the long-term consequences of TBI, the committee read and
evaluated some 1,900 studies that made up its literature base, and it developed criteria for
inclusion of studies to inform its findings. It is clear that brain injury, whether penetrating or
closed, has serious consequences. The committee sought to detail those consequences as clearly
as possible and to provide a scientific framework to assist the brave men and women who have
fought in OEF and OIF as they return home. We are honored to have been of service.
I am deeply appreciative of the expert work of our committee members and their
extraordinary commitment to the task at hand. The committee extends its appreciation to the
many people who presented information at its open meeting and to the IOM staff. In particular
we would like to thank Renee Wlodarczyk, Jen Saunders, and Naoko Ishibe who helped with a
myriad of tasks including literature searches, retrieving articles, entering data into the numerous
tables in the document, and for their contributions in the development of several chapters of the
report. We appreciate Joe Goodman’s attention to our meeting and travel needs; and to Carolyn
Fulco for her guidance and oversight.
George W. Rutherford, MD, AM
Chair, Committee on Gulf War and Health: Brain Injury in Veterans and Long-Term Health
Outcomes
xiii
OCR for page R1
xiv