Hyperbaric oxygen therapy (HBOT) markedly reduces multiple symptoms of persistent postconcussion syndrome (PPCS) following mild traumatic brain injury (mTBI), results from a randomized controlled crossover study show.
In civilians and military veterans with mTBI/PPCS, HBOT led to significant improvement in postconcussion symptoms, memory/cognition, behavioral/emotional problems, and sleep, resulting in significant improvement in patients' quality of life.
"This study is the culmination of 31 years of clinical treatment and research on hyperbaric oxygen for TBI," lead investigator Paul Harch, MD, clinical professor of medicine, Louisiana State University Health Sciences Center, New Orleans, told Medscape Medical News.
"It's also the first study that looked at both veterans and civilians, and the results really recapitulated what our experience has been," Harch said.
The study is published in the March issue of Medical Gas Research.
HBOT has been used to help with wound healing. "Over time, we have learned that traumatic brain injuries are considered to be wounds to the brain, which makes [HBOT] a scientifically logical application to this kind of injury," Harch said in a news release.
The study included 63 civilian and military patients who had been experiencing PPCS for an average of 4.6 years after being injured and who had not previously undergone treatment ― the longest average delay to treatment of any of the mTBI/PPCS HBOT studies to date.
Participants were randomly assigned either to a group that received 40 HBOT treatments at 150 kPa for 60 minutes once daily 5 days per week for 8 weeks, or to a control group that received no treatment for the same period, after which the control group crossed over to the HBOT group.
All participants underwent symptom assessment, as well neuropsychological and psychological testing, before and after treatment or control period. Participants were retested 2 months after the last HBOT session. Fifty patients completed the protocol with primary outcome testing.
With HBOT, there was a 26.3-point decrease in the Neurobehavioral Symptom Inventory PPCS symptom score (a primary outcome). For the control group, there was a 2.5-point decrease (P < .0001).
Compared with no treatment, HBOT also led to statistically significant improvement in memory, overall cognitive function, depression, anxiety, posttraumatic stress disorder (PTSD) symptoms, quality of life, and quality of sleep, as assessed using validated measures.
The researchers note that 83% of the HBOT group experienced an improvement in headaches, which was the index inclusion criteria symptom for the study; 33% of the control patients experienced worsening of headaches.
"This symptom has been identified as a primary symptom in TBI, the sole symptom distinguishing TBI/PPCS from PTSD, and is a surrogate marker for brain wounding in mTBI. The reduction in headache underscored that HBOT was treating TBI in this study and not just symptoms," they note in their article.
After crossing over to HBOT, the control group subsequently experienced "near identical and statistically indistinguishable improvements," the researchers report.