The number one cause of concussions for military service academy cadets and midshipmen in comparison to National Collegiate Athletic Association student-athletes is football, according to the NCAA-Department of Defense Concussion Assessment, Research and Education (CARE) Consortium.

Football accounts for more than half of all sports-related concussions, known as mild traumatic brain injury, and the sport has the highest incidence rate.

Girls' soccer accounts for the most concussions among women’s sports and has the second-highest incidence rate overall.

The NCAA has partnered with the Uniformed Services University in Bethesda, Maryland, since 2014 to synergize the efforts of the CARE Consortium with the Service Academy Longitudinal mTBI Outcomes Study (SALTOS). This has allowed the research group to track the number and incidence of concussion in college athletes, including those enrolled in the U.S Army Military Academy, U.S. Naval Academy; the U.S. Air Force Academy, and the U.S. Coast Guard Academy.

“The Uniformed Services University remains privileged to be part of the CARE Consortium, the largest study of its kind to examine the longitudinal effects on brain health of mild traumatic brain injury, known as concussion, and repetitive head impact exposure,” said Dr. Paul Pasquina, chair of the department of physical medicine & rehabilitation at the Uniformed Services University of the Health Sciences, and chief of the department of physical medicine and rehabilitation at the Walter Reed National Military Medical Center.

He is one of four lead principal Investigators in the CARE Consortium.

“The level of ‘team science’ we have witnessed in collecting and analyzing this massive dataset has been inspiring,” Pasquina said. “While we are proud of the discoveries that have been made to date, we remain committed and poised to advance our knowledge to improve the care of those who are affected by brain injury, particularly those in uniform.”

CARE and the CARE-SALTOS Integration (CSI) study have enrolled more than 53,000 cadets, midshipmen, and NCAA student-athletes from more than 30 different colleges, universities, and military service academies. These enrollees have participated in nearly 100 different sports, various recreational activities, and a variety of different military training activities across the services that have exposed many to repetitive head impact or concussion. To date, there have been more than 5,500 participants in the study who have sustained a sports-related concussion. This is the world’s largest study on sports-related concussion.

CARE-SALTOS Integrated Study

Building on its success, CARE and SALTOS have integrated their research objectives into the CSI study, which was funded to follow enrollees after graduation from their respective university or service academy to allow the researchers to examine the intermediate and long-term effects of concussion and repetitive head impact exposure on brain health.

Former CARE study participants who have graduated or left their undergraduate programs are participating in remote, online surveys, in-person assessments, or merging of their CARE-SALTOS data with their electronic health records.

The CARE website states the CSI study will continue the strategic partnership to develop prototypes and create best models to predict a person’s risk of developing long-term neurological health problems associated with concussion/mTBI and head impact exposure. This step is critical in preventing the long-term effects of repetitive brain injury in warfighters, athletes, and other individuals at highest risk, the website says.

Warfighters Benefit, Not Just Athletes

The CSI Consortium is an unprecedented opportunity to advance concussion science in every at-risk population, according to the website.

To that end, the study has added a new group of enlisted military personnel with high blast-exposure risk to study differences that might exist between this population and those already recruited for the study, including civilian and military students. This will address key gaps in brain injury science and directly align with the priorities of the DOD Warfighter Brain Health Initiative and Defense Health Agency TBI-related objectives, according to the Consortium website.

Results from the CSI study will have direct impact on current assessment, diagnosis, and management of concussion in military service members and athletes, according to the Consortium website. The decade-long partnership has yielded evidence on the natural history of clinical and neurobiological recovery after acute concussion, as well as identifying which factors are most strongly associated with recovery, the website says.

Also explored has been the risks for bad outcomes in academy members and NCAA student-athletes, according to the website.

Post-Exposure May Be More Important Than Pre-Injury Assessments

While recruitment continues on military installations, there have been several findings within the NCAA cohort that are directly translatable to the military population, said Valerie Trabosh DiVito, DHA TBI research portfolio manager, and civilian deputy director, Military Operational Medicine Research Program for the U.S. Army Medical Research and Development Command at Fort Detrick, Maryland. DiVito holds doctorates in biochemistry and molecular and cellular biology with post-doctoral training in neuroscience and TBI using animal models.

Socioeconomic status, thinking, and the ability to balance oneself were part of pre-injury assessments, yet the predictability of these assessments was not significant, according to DiVito.

In the military, “similar inferences could be made perhaps indicating that the focus should not be on pre-injury screening and targeting but rather post-exposure assessment,” DiVito said.

She also cited several peer-reviewed studies that “support the assumption that concussion presents differently in each patient and better assessment could inform individualized management strategies.”

Additionally, the CARE Consortium has produced preliminary data on concussion recovery as it relates to race, sex, and socioeconomic status, which all have correlates in the military population and “should be the focus of future research considerations,” she added.

Return-to-Duty Timelines and Other Lessons Learned

“While return-to-play and return-to-duty are not alike in all situations, there are core similarities that suggest findings in a student-athlete population could inform return-to-duty protocols in military operations,” DiVito said.

For example, concussion protocols for return-to-duty, return-to-learning, and return-to-play are used at the military academies, on the battleground, and in training. These protocols provide improved tools to predict recovery time and the long-term prognosis after concussion or repetitive head impact exposure.

A late 2023 publication from the CARE Consortium “provided evidence that return-to-activity protocols could be implemented more effectively based on post-injury symptomatology. Incorporating this information into military development efforts could aid in more efficient return-to-duty assessments and guidelines resulting in fewer lost duty days,” DiVito observed.

A “key deliverable from the research will be the ability to more precisely determine the diagnostic and prognostic applications of fluid and imaging biomarkers for concussion,” according to the CSI study mandate.

In the latter part of the CSI study, the Consortium will look at magnetic resonance imaging and biomarker identification and validation. “Combining knowledge from cognitive and physical assessments with that of imaging and biomarker assessment could produce incredible power to manage concussion recovery on an individual basis with effective results” DiVito predicted.

“As the level of evidence builds for these protocols, the military can shift its focus to phased implementation to ensure that the return on investment over the current standard of care is indeed positive and that service members continue to receive high-quality care after injury while optimizing brain health holistically over a service member’s career continuing through veteran care,” she said.

There have been advances made since the Consortium’s establishment. These include:

• History of multiple concussions is associated with longer recovery time after subsequent injury, as well as an increased burden in chronic post-concussive and psychological health symptoms
• Acute changes in brain structure, function, and neurobiology are detectable on advanced imaging and protein-related biomarkers after concussion, persist beyond the window of observed clinical recovery, and remain evident at least six months after injury
• Changes in brain structure and neurobiology are associated with repetitive head impact exposure, even in the absence of a diagnosed concussion
• There are two biomechanical pathways to concussion—magnitude of a single impact and cumulative head impact exposure prior to injury
• Evidence exists for individual differences in concussion threshold and individual variation in recovery
• Recovery trajectory after concussion is associated with post-injury level of TBI-associated protein-related biomarkers
• Widespread implementation of modern concussion management practices is associated with reduced risk of repeat concussion

Collaboration with Partners

The Consortium is expanding with the addition of other DOD partners, Pasquina said. These include the National Intrepid Center of Excellence for TBI at Walter Reed National Military Medical Center and the Defense Intrepid Network for TBI and Brain Health Intrepid Spirt Centers at Fort Liberty, North Carolina, Fort Cavazos, Texas, and Joint Base Lewis-McChord, Washington, as well as the Naval School Explosive Ordnance Disposal at Eglin Air Force Base, Florida, which trains joint service member students.