For Clinicians and Medical Providers

This page is for licensed clinicians, federal medical research and care institutions, and accredited continuing medical education providers. It is not a general-public information page, and it is not a download portal. The materials referenced below are provided through a vetted request process, in service of clinical care, evidence-based medical opinion preparation, and institutional clinical program development.

The Clinical Question

A growing peer-reviewed literature documents that occupational blast overpressure exposure — the cumulative, low-level pressure-wave burden carried by combat arms personnel routinely operating heavy weapons systems — produces measurable, persistent, and clinically diagnosable neurological harm. The evidence chain is now four-stage:

Acute and subclinical neurological injury at the time of exposure (Belding 2021; Woodall 2021).
Progressive neurovascular and structural changes over time, including blood-brain barrier disruption, neurovascular dysfunction, and white-matter integrity decline (Kilgore & Hubbard 2024; Hunfalvay 2022).
Clinically-confirmed VHA-diagnosed conditions persisting years after separation, identified through ICD diagnostic codes in administrative records (Belding 2023; Martindale 2025).
Distinctive post-mortem neuropathology, including interface astroglial scarring at gray-white matter junctions (Shively, Horkayne-Szakaly, Jones, Kelly, Armstrong, & Perl 2016), tauopathy and CTE-spectrum changes (Goldstein 2012), and blast-pattern axonal injury (Ryu 2014).

This evidentiary base is the substrate from which COWAC develops clinician-facing reference material. The full citation list and an open-access clinical synthesis are available below.

What COWAC Provides for Clinicians

COWAC has developed an Occupational Blast Overpressure Exposure: Clinician Reference — a comprehensive document covering blast overpressure physics and regulatory thresholds; the Department of Defense high-risk Military Occupational Specialty roster (DEPSECDEF Memorandum, August 8, 2024, Attachment 3); the cumulative exposure model and field-research threshold data; the pathophysiology of primary blast injury and progressive neurovascular dysfunction; clinical presentation across neurological, audiological, oculomotor, neuroendocrine, and psychiatric domains; emerging neurodegenerative associations; clinical assessment considerations including history-taking and validated assessment tools; VA service connection context and the at least as likely as not evidentiary standard; and a comprehensive ICD-10-CM coding reference, including the FY2026 Y37.A1 (low-level blast overpressure in military operations) code family and the Y37.A1XS sequela code that formally encodes the causal relationship between current condition and occupational blast exposure in the medical record.

The Reference is not publicly downloadable. Access is provided to qualifying clinicians and institutional partners through the request process described below.

Open-Access Clinical Synthesis

For clinicians evaluating whether to request the full Reference, the following synthesis describes what the literature establishes:

Occupational blast overpressure exposure is a recognized and increasingly documented occupational hazard producing acute and chronic neurological consequences in service members and veterans with sustained exposure histories. The clinical phenotype is heterogeneous and frequently misattributed to PTSD, mood disorders, or non-specific post-deployment health concerns. Core features include persistent post-concussive syndrome with cognitive impairment (memory, attention, processing speed); chronic headache and migraine; tinnitus and audiovestibular dysfunction; oculomotor and saccadic abnormalities; sleep disruption including sleep apnea; mood dysregulation; and, in some patients, neuroendocrine dysfunction. Emerging evidence implicates chronic LLB exposure in accelerated brain aging, white-matter integrity decline, and PET-detectable neuroinflammation along pathways consistent with neurodegenerative disease progression. Post-mortem neuropathology in chronically blast-exposed veterans demonstrates a distinct pattern of interface astroglial scarring, tauopathy, and axonal injury that does not appear in non-blast traumatic brain injury comparators.

Clinicians evaluating veterans with documented service in high-risk MOS designations such as artillery crews, infantry, infantry mortar crews, breachers, tankers, combat engineers, EOD personnel, and special operations forces who should consider repetitive low-level blast exposure as a relevant occupational history element with clinical and adjudicatory implications.

The August 8, 2024 DEPSECDEF Memorandum (OSD005281-24) identifies the specific MOS roster officially recognized by the Department of Defense as carrying elevated blast exposure risk.

The at least as likely as not (50/50 probability) standard the Department of Veterans Affairs applies in adjudicating service connection is, on the current evidentiary record, defensibly met for several conditions in patients with documented qualifying exposure histories. The Independent Medical Opinion is the conventional vehicle through which a treating clinician’s analysis enters the VA adjudication record.

Effective FY2026, ICD-10-CM code Y37.A1 (low-level blast overpressure in military operations) and its associated encounter and sequela subcodes (Y37.A1XA, Y37.A1XD, Y37.A1XS) provide a standardized mechanism for documenting occupational blast as the etiologic context in the medical record itself.

This synthesis is provided in COWAC’s voice. It is not a substitute for the underlying literature, and it does not replace independent clinical judgment.

Bibliography (Open Access)

The literature base anchoring the Clinician Reference is publicly available in the peer-reviewed record. Clinicians who do not request the Reference may consult the following primary sources directly:

Belding, J. N., Englert, R. M., Fitzmaurice, S., Jackson, J. R., Koenig, H. G., Hunter, M. A., Thomsen, C. J., & da Silva, U. O. (2021). Frontiers in Neurology, 12. Potential health and performance effects of high-level and low-level blast: A scoping review of two decades of research.
Belding, J. N., Kolaja, C. A., Rull, R. P., & Trone, D. W. (2023). Frontiers in Neurology, 14. Single and repeated high-level blast, low-level blast, and new-onset self-reported health conditions in the U.S. Millennium Cohort Study.
Goldstein, L. E., et al. (2012). Science Translational Medicine, 4(134). Chronic traumatic encephalopathy in blast-exposed military veterans and a blast neurotrauma mouse model.
Hunfalvay, M., Murray, N. P., Creel, W. T., & Carrick, F. R. (2022). Brain Sciences, 12(5), 679. Long-term effects of low-level blast exposure and high-caliber weapons use in military special operators.
Kamimori, G. H., et al. (2017). Shock Waves, 27, 837–847. Occupational overpressure exposure of breachers and military personnel.
Kilgore, M. O., & Hubbard, W. B. (2024). International Journal of Molecular Sciences, 25(1), 642. Effects of low-level blast on neurovascular health and cerebral blood flow.
Martindale, S. L., et al. (2020). Archives of Clinical Neuropsychology. Influence of blast exposure on cognitive functioning in combat veterans.
Martindale, S. L., Ord, A. S., Rule, L. G., & Rowland, J. A. (2021). Journal of Psychiatric Research, 143, 189–195. Effects of blast exposure on psychiatric and health symptoms in combat veterans.
Martindale, S. L., Belding, J. N., Crawford, C. D., & Rowland, J. A. (2023). Journal of Neurotrauma, 40, 2321–2329. Validation of military occupational specialty as a proxy for blast exposure using the Salisbury Blast Interview.
Martindale, S. L., Kolaja, C. A., Belding, J. N., Liu, L., Rull, R. P., Trone, D. W., & Rowland, J. A. (2025). Frontiers in Neurology, 16, 1599351. Blast exposure and long-term diagnoses among veterans: A Millennium Cohort Study investigation of high-level blast and low-level blast.
Rowland, J. A., & Martindale, S. L. (2024). Frontiers in Neurology, 15. Considerations for the assessment of blast exposure in service members and veterans.
Ryu, J., Horkayne-Szakaly, I., Xu, L., Pletnikova, O., Leri, F., Eberhart, C., Troncoso, J. C., & Koliatsos, V. E. (2014). Acta Neuropathologica Communications, 2, 153. The problem of axonal injury in the brains of veterans with histories of blast exposure.
Shively, S. B., Horkayne-Szakaly, I., Jones, R. V., Kelly, J. P., Armstrong, R. C., & Perl, D. P. (2016). The Lancet Neurology, 15(9), 944–953. Characterisation of interface astroglial scarring in the human brain after blast exposure: a post-mortem case series.
Wiri, S., et al. (2023). Frontiers in Neurology, 14. Dynamic monitoring of service members to quantify blast exposure levels during combat training using BlackBox biometrics blast gauges.
Woodall, J. L. A., et al. (2021). Military Medicine, 188(3-4). Repetitive low-level blast exposure and neurocognitive effects in Army Ranger Mortarmen.

Additional supporting citations (Carr, Trotter, Stone, Boutté, and others) are referenced within the works above and within the full Clinician Reference. Federal policy and regulatory documents — the DEPSECDEF Memorandum of August 8, 2024; DESR 6055.09; the FY18-FY20 NDAA blast research mandates; and the ICD-10-CM FY2026 code activation — are additionally cited in the Reference.

Three Tracks of Clinician Engagement

COWAC structures clinician engagement through three differentiated tracks. Please use the form that corresponds to your role.

For licensed clinicians actively involved in patient care, including private-practice neurologists, VA primary care providers, civilian TBI program clinicians, neuropsychologists, occupational medicine physicians, neuropathologists, audiologists, and accredited mental health providers evaluating blast-exposed veterans.

The full Clinician Reference is available to verified treating clinicians for use in clinical care, evidence-based medical opinion preparation, and institutional clinical program development, under the document’s standard use and distribution terms (described below). Requests are reviewed individually. Verification typically takes 3–5 business days.

Treating Clinician Request

Provider credentials work

Full name

First

Last

Professional credentials and degrees (e.g., MD, DO, PhD, PsyD, NP, PA)

National Provider Identifier (NPI)

Primary state(s) of licensure

Primary practice setting

Specialty

Institutional affiliation (if applicable)

Institutional email address

Brief description of the clinical question or patient population for which the Reference would inform your work

Attestations

I attest that I am a licensed clinician in active patient-care practice and that my interest in the Clinician Reference is to inform clinical care, evidence-based medical opinion preparation, or institutional clinical-program development. I am not requesting this material primarily for the production of compensation-and-pension medical opinions for fee.
I have read and accept the Use and Distribution terms below.

Requests are reviewed by COWAC leadership. You will receive a response within 3–5 business days. COWAC reserves the right to decline any request inconsistent with the organization’s mission and the terms of access described below.

For Department of Defense, Department of Veterans Affairs, and federally affiliated medical research and care institutions interested in coordination on blast-related neurological injury science, clinical care, or evidence translation.

This is an expedited pathway. COWAC welcomes direct contact from federal medical research and care institutions and treats these inquiries as priority engagements. Coordination relationships are governed by memoranda of understanding, institutional information-sharing frameworks, or equivalent federal-partner agreements as appropriate to the scope of the engagement.

For accredited CME providers, academic medical centers, professional societies, and institutional training programs interested in co-developing clinician education programming on occupational blast overpressure exposure.

COWAC does not operate a COWAC-accredited CME program. Where the Clinician Reference, in whole or in substantial part, would be incorporated into formal accredited continuing medical education programming, fee-based clinical training products, institutional credentialing curricula, or other derivative works generating revenue or carrying third-party institutional accreditation, a separate written co-development and licensing agreement governs the partnership. COWAC’s role in such partnerships is content authority and subject-matter expertise; the partner institution’s role is curriculum delivery, accreditation, and learner assessment.

Co-development and licensing agreements address scope of permitted use, permitted modifications, attribution requirements, quality-control review, revenue arrangements where applicable, term and termination, and ownership of derivative work. Specific terms are negotiated based on the scope and structure of the proposed partnership.

Ordinary citation of the Reference in scholarly publications, grand rounds presentations, journal articles, professional society newsletters, or institutional clinical communications does not require a licensing agreement. Use of the Reference in an institution’s internal clinical program development – including the development of internal training materials that are not separately accredited or fee-based – also does not require a licensing agreement.

Current and Prospective Coordination Partners

COWAC’s clinician-facing work is developed in awareness of, and where appropriate in coordination with, the federal medical research and care enterprise concerned with blast-related neurological injury. Active and prospective coordination relationships include:

Naval Medical Research Command (NMRC) and the University of Virginia — federally funded blast injury research study; COWAC’s founder, Timothy Grossman, serves on the community advisory board.
Uniformed Services University of the Health Sciences (USU) — including the Department of Pathology and the VA-DoD Brain Tissue Repository, where the post-mortem neuropathological literature anchoring much of COWAC’s evidentiary base originates.
Traumatic Brain Injury Center of Excellence (TBICoE), formerly DVBIC — the Department of Defense’s lead clinical entity on TBI care, education, and surveillance.
National Intrepid Center of Excellence (NICoE) — the Walter Reed-affiliated TBI and psychological health treatment center for active duty servicemembers. COWAC’s founder previously served as a subject matter expert with Wounded Warrior Project embedded at Walter Reed and at NICoE.
VA War Related Illness and Injury Study Center (WRIISC) — the VA’s national specialty program for post-deployment health concerns.
DoD Blast Injury Research Coordinating Office (BIRCO) — coordinator of the FY18-FY20 NDAA-mandated longitudinal blast pressure exposure study and the Blast Overpressure Studies (BOS) Working Group.

COWAC operates as a 501(c)(4) policy advocacy organization. Our role is to translate the science these institutions produce into legislative, regulatory, and clinical-practice change. We are not a research funder, a care provider, or a competitor to any of the institutions named above. Educational and research-translation initiatives are conducted in coordination with appropriate institutional partners.

Use and Distribution Terms

The Occupational Blast Overpressure Exposure: Clinician Reference is the copyrighted intellectual property of the Cohort of Overpressured Warfighters Action Council (COWAC). Access is granted to vetted clinicians and institutional partners under the following terms:

The Reference is provided for use in clinical care, evidence-based medical opinion preparation, institutional clinical program development, scholarly citation, and (for Track C partners) jointly developed and separately licensed continuing medical education programming.
Distribution of the Reference to third parties outside the recipient’s clinical practice or institutional program is not authorized without prior written permission from COWAC.
The Reference may not be incorporated, in whole or in substantial part, into formal accredited continuing medical education programming, fee-based clinical training products, institutional credentialing curricula, or other derivative works generating revenue or carrying third-party institutional accreditation, without a separate written co-development and licensing agreement with COWAC. Ordinary citation, scholarly reference, and institutional clinical use do not require a licensing agreement.
The Reference may not be incorporated into for-fee compensation-and-pension medical opinion services, claims-mill operations, or any program of practice whose primary function is the production of medical opinions for fee.
COWAC reserves the right to revoke access for misuse, including unauthorized distribution, incorporation into non-permitted commercial activity, or misrepresentation of COWAC’s role in derivative work.

These terms are not intended to constrain legitimate clinical use, scholarly citation, or institutional clinical program development. They are intended to protect the integrity of the Reference and to ensure that COWAC’s evidentiary work product serves the population for whom it was developed.

Questions regarding permitted use, citation, or licensing should be directed to COWAC leadership through the Track C inquiry form above or through the Contact page.

What COWAC Does Not Provide

COWAC does not file, prepare, or present individual claims before the VA or any other federal agency. We do not refer veterans to specific clinicians for fee-based services, and we do not operate an Independent Medical Opinion production service. Veterans pursuing service connection should work with an accredited Veterans Service Organization or accredited claims agent.