Department of Pediatrics Division of Genetics and Metabolism

What is high prepared oxygen therapy and how does this relate to the treatment of autism?

In the last decade, there has been increasing use of oxygen therapy in the treatment of a number of chronic diseases. The method is to administer oxygen to an individual under higher than normal atmospheric pressures. When this happens, there is an increased infusion of free oxygen into the tissues. In the case of blood, this free oxygen exists in a state different from that in which oxygen is typically bound to the hemoglobin molecule. The typical hyperbaric treatment involves using increased atmospheric pressures, usually up to three times normal, with increased oxygen concentrations that can go up to 100%. When increased atmospheric pressure is used associated with only a normal concentration of oxygen, 21%, then the term used is hyperbaric therapy (HBT). When oxygen at increased concentrations is used, the term HBOT is used. The diagram below illustrates these two terms and also provides a listing of the major purported, theoretical benefits of this treatment for autism.

Autism: hyperbaric oxygen therapy

First, let me say that there is no convincing evidence, using a controlled study, that any type of hyperbaric therapy provides sustained benefit to an individual with autism. However, there are a number of uncontrolled trials as well as anecdotal reports that indicate a treatment benefit. At present, the matter must be considered an unknown. The therapy is associated with minimal risk, for example one might sustain middle ear compression injuries due to atmospheric pressure changes.

The main underpinning that justifies such hyperbaric treatment is a group of studies that show apparent differences in regional brain metabolism and/or regional brain blood flow in individuals with autism. These studies have fueled the hypothesis that there could be problems with underutilization of oxygen in certain brain areas in autism. Accordingly, the provision of increased oxygen in the tissues, per se, (something theoretically delivered by high-pressure oxygen treatments) would be a logical correction or treatment for this type of oxygen depletion problem. Also, justification for hyper oxygen treatments as well involves a few studies that purport to find inflammatory changes at the cellular level in brains of individuals with autism. The presumption is that the effects of oxygen would augment any process of healing and correct or help correct this inflammation.

There is contradictory evidence as to how increased tissue oxygen might relate to the problem of free radical oxygen damage. In this sense, hyper oxygen therapy might be considered at odds to another treatment approach to autism which involves antioxidant use. Such antioxidant use is aimed at diminishing the damaging effects of free radical oxygen molecules or other types of abnormal oxidizing substances.