Blast Overpressure Longitudinal Study
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- This is an observational study: the protocol does not assign a study treatment.
- Who it may be relevant to
- Registry conditions: Low-level Blast Exposure. Basic parameters: 18 years — 50 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Blast Overpressure Longitudinal Exposure Study (BLES)
Overview
The goal of this observational study is to learn about the impact of low-level blast exposure in U.S. Special Operations Forces personnel. The main questions it aims to answer are: What advanced brain imaging changes are related to clinical presentation after low-level blast exposure? What are the relationships between low-level blast exposure and common groups of symptoms after concussion? Participants will: * Undergo advanced brain imaging * Answer questionnaires * Complete clinical tests * Provide blood, urine, and saliva samples * Wear blast sensors
Detailed description
Participants in this observational study are active-duty U.S. Special Operations Forces personnel between the ages of 18 and 50. This study is designed to characterize the neurological and clinical effects associated with repeated low-level blast exposure (LLBE) in this population. Concerns have emerged that cumulative exposure to sub-concussive blast overpressure (BOP), even in the absence of a diagnosable concussion, may be associated with subtle changes in brain structure and function over time. Due to the nature of their operational and training environments, Special Operations Forces personnel may experience repeated LLBE and are therefore an important population for longitudinal investigation.
Participation involves in-person assessments and data collection conducted over a period of approximately 4-5 years. The schedule of study activities includes baseline, daily, weekly, monthly, quarterly, and annual assessments. Baseline and annual study visits include advanced magnetic resonance imaging (MRI) and require travel to Walter Reed National Military Medical Center. Specifically, this study includes the use of the Microstructure Anatomy Gradient for Neuroimaging with Ultrafast Scanning (MAGNUS) 3.0 Tesla MRI.
Throughout the study period, participants complete standardized questionnaires and clinical assessments and provide biological samples, including blood, urine, and saliva, at specified intervals. Participants also contribute measures on a daily, weekly, monthly, quarterly, and annual basis. They will wear blast sensors throughout their participation in the study.
The total planned enrollment for the study is approximately 250 participants across multiple sites, with an estimated 60 participants enrolled at Fort Bragg, NC. Enrollment and follow-up are expected to occur over a 4-5 year period.
Primary outcome measures
- Effective axonal radii mapping [Time frame: At baseline and annually through study completion, an average of 5 years]
Secondary outcome measures (12)
- Ohio State University TBI Identification Method [Time frame: At baseline and annually through study completion, an average of 5 years]
- Concussion Clinical Profiles Screening [Time frame: At baseline and annually through study completion, an average of 5 years]
- Neurobehavioral Symptom Inventory [Time frame: At baseline and weekly through study completion, an average of 5 years]
- Headache Impact Test [Time frame: At baseline and weekly through study completion, an average of 5 years]
- modified Military Concussion Readiness Inventory for Dizziness and Balance [Time frame: At baseline and quarterly through study completion, an average of 5 years]
- Composite Autonomic Symptom Score (COMPASS) 31 [Time frame: At baseline and annually through study completion, an average of 5 years]
- Pittsburgh Sleep Quality Index [Time frame: PSQI at baseline and annually through study completion, an average of 5 years]
- Brief Pittsburgh Sleep Quality Index [Time frame: B-PSQI monthly through study completion (except at baseline and annually when the 18-item PSQI [see above] will be used), an average of 5 years]
- STOP-Bang [Time frame: At baseline and annually through study completion, an average of 5 years]
- Neck Disability Index [Time frame: At baseline and annually through study completion, an average of 5 years]
- PTSD Checklist for DSM-5 (PCL-5) [Time frame: At baseline and annually through study completion, an average of 5 years]
- General Anxiety Disorder (GAD-7) [Time frame: At baseline and annually through study completion, an average of 5 years]
Eligibility criteria
Inclusion criteria
- Active duty
- U.S. SOF personnel
- 18-50 years old
Exclusion criteria
- Subjects will be excluded only if their participation will significantly interfere with validity of data collection or safety during the study (e.g., they have conditions that might result in harm or injury during research procedures).
- Example: pregnancy (balance considerations)
- Example: being unable to undergo MRI testing (i.e., they have non-MRI compatible devices, imbedded metal fragments such as shrapnel, and/or severe claustrophobia; these MRI contraindications will be screened using an MRI Safety Questionnaire)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Observational model
- Cohort
Study locations
United States · 3 centers
- Walter Reed National Military Medical Center — Bethesda
- Fort Bragg — Fort Bragg
- Wilford Hall Ambulatory Surgical Center — San Antonio
Identifiers
NCT: NCT07606651 · 25-21750 · HU00012520052