Traumatic Brain Injury (TBI) is the most common injury that service members experience in the combat settings of Iraq and Afghanistan, especially in those sustaining multiple exposures.
The mechanisms of injury included blasts or explosions, falls, motor vehicle accidents, and fragment, shrapnel, and bullet wounds. In one survey of more than 2,000 army infantry soldiers, performed three to four months after their return from a one-year deployment in Iraq, 5% reported injuries with loss of consciousness and 10% reported injuries with altered consciousness.
Symptoms of TBI
Acutely, the symptoms of concussion are confusion and amnesia, sometimes with, but often without, preceding loss of consciousness. These symptoms may be apparent immediately after the head injury or may appear several minutes later. The alteration in mental status characteristic of concussion can occur without loss of consciousness. Seizures are uncommon in mild TBI, and problems such as limb weakness do not occur with mild TBI.
The majority of mild TBI patients develop headache, dizziness, neuropsychiatric symptoms, and cognitive impairments, which may continue for weeks to months with up to 25% of patients for over six months.
Individuals with a history of chronic (>1-year prior) mild TBI often develop emotional and cognitive dysfunction, including disturbances in mood (depression, suicide) and alterations in sleep (i.e., poor quality, changes in sleep-stage proportions), often culminating in inability to carry out ordinary daily activities, work responsibilities, and standard social relationships. Sleep complaints often occur, including insomnia, difficulty maintaining sleep, early morning awakenings, and nightmares.
Despite considerable research and substantial changes in the acute care of combat-related TBI in U.S. military personnel in recent years, trends in clinical outcomes have changed very little.
There is no effective treatment or pharmaceutical intervention in the daily clinical practice for TBI. Intensive therapy and rehabilitation programs are considered essential for maximizing quality of life, but are often only partially successful. Various novel approaches such as hyperbaric oxygen have demonstrated potential but remain unproven, thus highlighting a significant unmet need. The intensive search for new methods to provide sustained relief affected patients continues.
Using Stem Cells to Treat TBI
The mechanisms of stem cell-related repair in TBI have been studied with various types of cells, including those taken from adipose tissue and bone marrow. Over the last seven to eight years, clinical studies of stem cell-based TBI treatment have been few, most targeting patients either in the acute stage with intravenous infusion, injection into the spinal canal, or direct injection into the brain (requiring surgery). Fewer have addressed the chronic mild TBI patient.
Increasingly, patients seek treatment options outside of their traditional healthcare environments, many to receive stem cells. Stem cell clinics vary with respect to types of patients treated and types of cells used; most do not specify doses and the means of administration and do not follow guidances or common standards for stem cell product production. The development of stem cell clinics is increasing globally. Concerns have been expressed regarding marketing of services and implementing and monitoring safety standards and outcomes.
A significant shortcoming of most stem cell clinics is the failure to collect follow-up data, a result often ascribed to logistical and financial constraints of having patients return for multiple visits from geographically remote areas. The commitment to assessing long-term outcomes is of critical importance. To our knowledge of the clinics cited above, few if any incorporate structured mechanisms for long-term patient follow-up in TBI patients.