Reduced brain activity in the frontal lobes of the brain and in the hippocampus showed improvement after Hyperbaric Oxygen Therapy (HBOT). Photo: Shamir Medical Center

Israeli scientists at the Tel Aviv University have found that oxygen therapy can significantly reduce post-traumatic stress disorder (PTSD) symptoms, according to a study conducted among Israel Defense Force veterans.

During a controlled clinical trial, researchers led by Tel Aviv University and the Shamir Medical Center identified brain wounds in IDF veterans with treatment-resistant PTSD, which they relieved by using hyperbaric oxygen therapy (HBOT).

An assessment of symptoms and brain scans post-treatment showed “functional and structural improvement (…) in the non-healing brain wounds that characterize PTSD.” The peer-reviewed study was published Tuesday in the scientific journal PLOS One.

“Our results indicate that exposure to severe emotional trauma can cause organic damage to the brain,” said Prof. Shai Efrati, leading the research. “Today we understand that treatment-resistant PTSD is caused by a biological wound in brain tissues, which obstructs attempts at psychological and psychiatric treatments.”

The researchers noted that the success rate of current PTSD treatments, including trauma-focused psychotherapy and medication, is poor. Hyperbaric treatment aims to improve the supply of oxygen to the brain to activate the generation of new blood vessels and neurons. Treatments are conducted in a hyperbaric chamber, where atmospheric pressure is higher than sea-level pressure and the air is rich with oxygen.

“The treatment induces reactivation and proliferation of stem cells, as well as generation of new blood vessels and increased brain activity, ultimately restoring the functionality of the wounded tissues,” Efrati explained.

The results of the trial “demonstrate for the first time that direct biological treatment of brain tissues can serve as a tool for helping PTSD patients,” he asserted.

PTSD affects people who have gone through a traumatic experience such as a natural disaster, a serious accident, a terrorist act, or combat. Symptoms include intrusive thoughts, nightmares, sleeping disorders and flashbacks of past traumatic events. For veterans of war, it can often lead to depression, anxiety, and other issues once they return home and try to readjust to civilian life. According to the World Health Organization (WHO), almost 4 percent of the global population, and 30 percent of all combat soldiers, develop PTSD.

The trial, carried out between March 2018 and April 2019, included 35 combat veterans between 25 to 60 years old, who had suffered at least four years from PTSD that was resistant to both psychiatric medications and psychotherapy. Veterans were divided into two groups: one treated with HBOT for a total of 60 daily sessions, five days a week, while the other serving as a control group for the three-month trial.

“Following a protocol of 60 treatments improvement was demonstrated in all PTSD symptoms, including hyper-arousal, avoidance, and depression,” said Dr. Keren Doenyas-Barak. “We believe that in most patients, improvements will be preserved for years after the completion of the treatment.”

Going forward, Efrati believes that the results of the study “paves the way to a better understanding of the connection between mind and body.” The findings may also help diagnose PTSD, which currently is based on personal reports — leading to disagreements between PTSD veterans and local authorities responsible for treating them.

“At present we are conducting continuing research in order to identify the biological fingerprint of PTSD, which can ultimately enable the development of innovative objective diagnostic tools,” Efrati said.