Breanna R. Roberts, MA, BCBA, LBA, Stacha C. Leslie, M.Ed., BCBA, LBA, and Thomas Zane, PhD, BCBA-D
Department of Applied Behavioral Science, University of Kansas

Is there science behind thatApproximately 1 in 36 children have been identified as having a diagnosis of autism spectrum disorder (ASD), an increase from 1 in 44 children in 2018 (Maenner et al., 2023). As rates of ASD diagnoses increase, so has the use of alternative therapies (Brondino et al., 2015). One of these alternative therapies is the use of Hyperbaric Oxygen Therapy (HBOT; Rossignol & Rossignol, 2006), purportedly designed to treat both genetic and environmental risk factors contributing to an individual’s unique presentation of ASD, such as neuroinflammation, gastrointestinal inflammation, and decreased blood flow to the brain.

What is Hyperbaric Oxygen Therapy?

HBOT is defined as the “treatment of a disease or medical condition by the inhalation of near-100% (at least 95%) medical grade oxygen at pressures greater than 1 atmosphere absolute (ATA).” (Undersea and Medical Society, n.d.). Each treatment session consists of two cycles in a hyperbaric oxygen chamber and is conducted once per day for a variable number of sessions, depending on the condition. The first cycle includes the compression cycle during which the pressure in the chamber increases slowly to allow the pressure in the ears and sinuses to equalize. Once the hyperbaric chamber has reached its target pressure, the second cycle begins. This pressure is administered for approximately 45-300 minutes while the patient sits or lies in the chamber, taking deep breaths. Currently, HBOT has been recommended by the FDA as an effective treatment for several conditions, including severe anemia, burns, carbon monoxide poisoning, wound healing, and decompression sickness (U.S. Food and Drug Administration, 2021). Benefits of HBOT used for FDA-approved disorders and illnesses include increasing oxygen concentration in body tissue, stimulation of new blood vessel growth in areas with less circulation, and treatment of infections by improving white blood cell function (The University of Kansas Health System, n.d.).

More recently, hyperbaric chambers have become widely available in non-Undersea Hyperbaric Medical Society (UHMS) accredited locations (e.g., “wellness centers” or “health spas”) and are often advertised to treat a wide range of disorders and illnesses that have not been recognized by the FDA (e.g., ASD, Lyme Disease, Arthritis, Long COVID, etc.). Both the FDA and the UHMS caution the use of HBOT devices for the treatment of disorders or illnesses other than those cleared by the FDA. Additionally, the FDA and UHMS recommend only accessing hospitals or facilities that have been inspected and accredited by the UHMS, as well as ensuring HBOT is prescribed and supervised by physicians with appropriate training (Undersea and Medical Society, n.d.). Finally, the FDA suggests that there are many potential risks associated with the non-regulated use of HBOT, including ear and sinus pain, middle ear injuries (including tympanic membrane rupture), temporary vision changes, and lung collapse (U.S. Food and Drug Administration, 2021). Additionally, non-regulated hyperbaric chambers pose a fire risk due to the high oxygen concentrations needed during HBOT (Undersea and Medical Society, n.d.).

What are the Purported Uses of Hyperbaric Oxygen Therapy for Children with Autism?

The Centers for Disease Control and Prevention (CDC) describes ASD as a developmental disability in which people diagnosed may have difficulties with social communication and interaction and restricted or repetitive behaviors or interests (Centers for Disease Control and Prevention, 2022). These difficulties may be observed as limited social interactions, repeating words or phrases, getting upset by minor changes, and delayed language, movement, and learning skills (Centers for Disease Control and Prevention, 2022). In both animal and human models, HBOT has been suggested as an intervention to treat phenomena observed in individuals with ASD, including neuroinflammation, gastrointestinal inflammation, and immune dysregulation (Bjorklund et al., 2016; Bjorklund et al., 2020, Boddaert et al., 2002; Doenyas, 2018; Gutsaeva et al., 2006; Rose et al., 2018; Rossignol, 2007; Rossignol & Fry, 2012), and by extension, how the symptoms manifest in individuals diagnosed with ASD. For example, some researchers hypothesize HBOT could help with symptoms related to language development, repetitive and rigid behaviors (e.g., desire for sameness), and recognition of emotions and facial expressions (Podgórska-Bednarz & Perenc, 2021) by increasing blood flow to areas of the brain associated with those behaviors.

Does Science Support Hyperbaric Oxygen Therapy?

In our 2016 review of the research examining the merits of HBOT, there was not compelling evidence to support its use (Harrison & Zane, 2016). Most of the current research supporting the use of HBOT as a treatment for ASD has consisted of small studies of 20-30 participants or case studies. For example, Lasheen et al. (2019) evaluated the effectiveness of using HBOT to improve auditory attention and memory in 20 participants aged 8-14 years with and without ASD. The children were split into an intervention and control group, matched to specific demographic factors. The authors first obtained a detailed personal and medical history and conducted two other audiological evaluations for each participant. Second, both groups were exposed to two different tones in random order with one tone occurring less frequently (i.e., the “rare” stimulus) than the other (i.e., the “standard” stimulus). The purpose of the assessment was for the participant to identify the rare stimulus by counting it. Third, HBOT sessions were conducted at 1.5 atmosphere (atm) and 100% oxygen for 45 minutes daily for 40 sessions per child in the intervention group only. Last, the audiological evaluations were re-conducted with the intervention group. Reported outcomes suggested statistically significant differences for both groups for pre- and post-HBOT, with the intervention group showing a decrease in latencies to recognition of the rare tone and with decreased amplitudes during the post-HBOT audiological tests. However, the authors did not conduct any behavioral assessments prior to the start of HBOT sessions and it is unknown what other therapies these participants may have been      receiving. Additionally, audiological tests were not re-administered for the control group after the intervention group received HBOT. Therefore, it may be difficult for readers to determine the exact cause of the improvements in each group. For example, the performance of the control group may have improved as a result of more exposure to the testing format or stimuli, or other therapies that the intervention group may have been receiving.

Hooper (2020) evaluated the use of HBOT to decrease neuroinflammation and clinical symptoms of ASD (e.g., rigid behaviors, difficulty recognizing emotions, etc.) in a 7-year-old male diagnosed with ASD, described as “high-functioning ASD, non-social, non-verbal” (p. 118). First, the participant changed to an adapted ketogenic diet and supplements to assist with modulation of inflammatory cytokines. Next, HBOT sessions were conducted at 1.8 ATA with 100% oxygen and regular air brakes. Hooper reported that after HBOT, the participant made “extraordinary improvement” and now attended a regular school. However, there are a few limitations to discuss relevant to this case study. Primarily, no behavioral assessments were conducted prior to the implementation of HBOT. Objective and quantifiable data would have allowed readers to determine if HBOT contributed to the “extraordinary improvement” observed with this participant. However, no objective or quantifiable data was provided to define what consisted as an “extraordinary improvement” for the participant. Last, it is unknown what other therapies this participant might have been receiving and there was no control group or participant. Thus, it is difficult for readers to identify whether improvements were due to HBOT or other therapies that the participant may have been receiving.

Current research that does not support the use of HBOT as a treatment for ASD consists of smaller-scale studies as well as reviews of previous HBOT research. The best use of experimental control to evaluate the efficacy of HBOT were Lerman et al. (2009) and Jepson et al. (2011). The two studies had a total of 19 participants aged 2-10 years with ASD, each receiving a total of 40 HBOT sessions. Data were collected on symptoms of ASD, including stereotypy and aberrant behaviors (e.g., SIB, aggression, disruption, etc.) and adaptive behaviors (e.g., initiations and responses, spontaneous communication, and task engagement). The outcomes of both studies demonstrated that HBOT failed to show any robust changes in the measured behaviors. However, both studies have limitations that should be noted. First, all participants were receiving ongoing behavior analytic services during the duration of the studies. Therefore, increases in adaptive behaviors and decreases in aberrant behaviors could have resulted from behavior analytic intervention and not HBOT. Additionally, no biochemical data (e.g., markers of inflammation or oxidative stress) were collected during either study. Thus, it is hard to determine how HBOT may have affected the biological processes of these participants.

There have been a number of reviews (Brondino et al., 2015; Ghanizadeh, 2012; Goldfarb et al., 2016; Halepoto et al., 2014; Harrison & Zane, 2016; Klein & Kemper, 2016; Podgorska-Bednarz & Perenc, 2021; Zhukova et al., 2020) examining the efficacy of HBOT to improve ASD symptoms. These reviews all had similar findings, indicating weak evidence for its use for individuals with ASD. However, Podgorska-Bednarz and Perenc (2021) noted several limitations. First and foremost, the authors did not assess the strength of the evidence presented in each article. Therefore, it is more difficult for readers to conclude the effects of HBOT across articles. Second, this review only considered studies including children. That is, HBOT research conducted with adults was not included. However, despite some studies touting benefits such as improvements in socialization, language, attending, and a reduction in problem behaviors (Buckley, 2005; Rossignol & Rossignol, 2006), HBOT studies have shown inconsistent results overall. The results of these reviews, in conjunction with recommendations from the CDC and UHMS, suggest that HBOT should not be used as a treatment for ASD symptoms.

What Else Should We Consider?

HBOT can be very costly. In fact, the use of HBOT in a medical facility is estimated to cost up to $150 per hour (Jepson et al., 2011). Second, if caregivers want to implement HBOT in their homes, investing in hyperbaric oxygen chambers may range in costs from $8,000 to $28,000. The third cost is found in the time that is spent receiving, prepping, and traveling to receive HBOT. The time spent preparing, traveling, and in HBOT sessions are times in which behavior analysis, speech therapy, and occupational therapy could have otherwise been available.

Although we do not recommend HBOT as an evidence-based treatment for ASD, we suggest readers defer to the FDA and UHMS for best-practice suggestions on the use of HBOT. Currently, there is not enough evidence to suggest a causal relationship between HBOT and positive changes in ASD symptomatology. Therefore, given the limited amount of strong empirical evidence and the associated risks and costs of HBOT, we suggest that no further research on HBOT as a treatment for ASD be conducted. In its place, we urge treatment providers, caregivers, and individuals with ASD to pursue empirically derived and evidence-based practices to address symptoms of ASD. These include treatment and intervention services such as, but not limited to, Applied Behavior Analysis (ABA), Speech and Language Therapy, Occupational Therapy, and Cognitive-Behavior Therapy (CBT; Centers for Disease Control and Prevention, 2022). Additionally, we urge clinicians and researchers to address instances of evidence denial and promotion of pseudoscience using a framework described by Smith and MacDonald (2017) to ensure the best empirical evidence is available to treatment providers, caregivers, and individuals with ASD.

What is the Gist?

As was the case eight years ago (Harrison & Zane, 2016), we do not recommend the use of HBOT as a scientific treatment for ASD at this time. Limited research has been conducted on the efficacy of HBOT as a treatment for this diagnostic category. Although some studies report improvements in socialization, language, attending, and challenging behaviors (Buckley, 2005; Rossignol & Rossignol, 2006), these results are inconsistent across studies. Due to mixed results in studies evaluating HBOT and associated risk and costs, there is not currently enough evidence to suggest that HBOT is an effective treatment for ASD.

References

Abdel-Tahman, E. A., Zaky, E. A., Aboulsaoud, M., Elhossiny, R. M., Youssef, W. Y., Mahmoud, A. M., & Ali, S. S. (2021). Autism spectrum disorder (ASD)-associated mitochondrial deficits are revealed in children’s platelets but unimproved by hyperbaric oxygen therapy. Free Radical Research 55(1), 26-40. https://doi.org/10.1080/10715762.2020.1856376

Boddaert, N., & Zilbovicius, M. (2002). Functional neuroimaging and childhood autism. Pediatric Radiology, 32(1), 1–7. https://doi.org/10.1007/s00247-001-0570-x

Bjørklund, G., Meguid, N. A., El-Bana, M. A., Tinkov, A.A., Saad, K., Dadar, M., Hemimi, M., Skalny, A. V., Hosnedlová, B., Kizek, R., Osredkar, J., Mauricio, A. U., Fabjan, T., El-Houfey, A. A., Katuzna-Czaplinska, J., Gatarek, P., & Chirumbolo, S. (2020). Oxidative stress in autism spectrum disorder. Molecular Neurobiology, 57, 2314–2332. https://doi.org/10.1007/s12035-019-01742-2

Bjorklund, G., Saad, K., Chirumbolo, S., Kern, J. K., Geier, D. A., Geier, M. R., & Urbina, M. A. (2016). Immune dysfunction and neuroinflammation in autism spectrum disorder. Molecular Neurobiology, 55(5), 2314–2332. https://doi.org/10.21307/ane-2017-025

Brondino, N., Fusar-Poli, L., Rocchetti, M., Procenzani, U., Barale, F., & Politi, P. (2015). Review article: Complementary and alternative therapies for autism spectrum disorder. Evidence-Based Complementary and Alternative Medicine, 1-31. https://doi.org/10.1155/2015/258589

Buckley, J. A. (2005). How mild hyperbaric oxygen therapy works and why it is good for our children. Medical Veritas, 2, 647. https://communityhyperbaric.com/wp-content/uploads/2013/11/How-mild-hyperbaric-oxygen-therapy-works-and-why-it-is-good-for-our-children.pdf

Centers for Disease Control and Prevention. (2022, March 9). Treatment and intervention services for autism spectrum disorder. https://www.cdc.gov/ncbddd/autism/treatment.html

Doenyas, C. (2018). Gut microbiota, inflammation, and probiotics on neural development in autism spectrum disorder. Neuroscience, 15, 271–286. https://doi.org/10.1016/j.neuroscience.2018.01.060

Ghanizadeh, A. (2012). Hyperbaric oxygen therapy for treatment of children with autism: A systematic review of randomized trials. Medical Gas Research 2(13), 1-8. https://doi.org/10.1186/2045-9912-2-13

Goldfarb, C., Genore, L., Hunt, C., Flanagan, J., Handley-Derry, M., Jethwa, A., Jones-Stokreef, N., Kirkpatrick, S. M. L., Richards, A., Rojnica, L., Schwartz, C., Shawn, D., Superina-Bell, D., Young, E., & Anagnostou, E. (2016). Hyperbaric oxygen therapy for the treatment of children and youth with autism spectrum disorders: An evidence-based systematic review. Research in Autism Spectrum Disorders 29-30, 1-7. https://doi.org/10.1016/j.rasd.2016.05.004

Gutsaeva, D. R., Suliman, H. B., Carraway, M. S., Demchenko, I. T., & Piantadosi, C. A. (2006). Oxygen-induced mitochondrial biogenesis in the rat hippocampus. Neuroscience, 137, 493–504. https://doi.org/10.1016/j.neuroscience.2005.07.061

Halepoto, D. M., AL-Ayadhi, L. Y., A. & Salam, A. A. (2013). Therapeutic use of hyperbaric oxygen therapy for children with autism spectrum disorder. Journal of the College of Physicians and Surgeons Pakistan 24(7), 508-514. https://pubmed.ncbi.nlm.nih.gov/25052976/

Harrison K. L., & Zane, T. (2016). Is there science behind that?: Hyperbaric oxygen therapy. Science in Autism Treatment, 13(4), 28-33.

Hooper, M. R. (2020). Autism and hyperbaric oxygen therapy. Medical and Clinical Research, 5(6), 118-121. https://www.medclinrese.org/open-access/autism–hyperbaric-oxygen-therapy.pdf

Jepson, B., Granpeesheh, D., Tarbox, J., Olivia, M. L., Stott, C., Braud, S., Helen Yoo, J., Wakefield, A., & Allen, M. S. (2011). Controlled evaluation of the effects of hyperbaric oxygen therapy on the behavior of 16 children with Autism spectrum disorders. Journal of Autism and Developmental Disorders, 41, 575-588. https://doi.org/10.1007/s10803-010-1075-y

Klein, N., & Kemper, K. (2016). Integrative approaches to caring for children with autism. Current Problems in Pediatric and Adolescent Health Care, 46, 195-201. https://doi.org/10.1016/j.cppeds.2015.12.004

Lasheen, R. M., Hassan Abu-Zaid, M., & Abd Al Hamed Tabra, S. (2019). Evaluation of auditory attention and memory skills in autistic children after hyperbaric O2 treatment. Egyptian Journal of Ear, Nose, Throat, and Allied Sciences, 20(2), 60-66. http://doi.org/10.21608/EJENTAS.2019.10954.1087

Lerman, D. C., Sansbury, T., Hovanetz, A., Wolever, E., Garcia, A., O’Brien, E., & Adedipe, H. (2009). Using behavior analysis to examine the outcomes of unproven therapies: An evaluation of hyperbaric oxygen therapy for children with autism. Behavior Analysis in Practice, 1(2), 50-58. https://doi.org/10.1007/BF03391728

Maenner, M. J., Warren, Z., Robinson Williams, A., Amoakohene, E., Bakian, A. V., Bilder, A. A., Durkin, M. S., Fitzgerald, R. T., Furnier, S. M., Hughes, M. M., Ladd-Acosta, C. M., McArthur, D., Pas, E. T., Salinas, A., Vehorn, A., Williams, S., Esler, A., Grzybowski, A., Hall-Lande, J., Nguyen, R. H., Pierce, K., Zahorodny, W., Hudson, A., Hallas, L., Clancy Mancilla, K., Patrick, M., Shenouda, J., Sidwell, K., DiRienzo, M., Gutierrez, J., Spivey, M. H., Lopex, M., Pettygrove, S., Schwenk, Y., Washington, A., & Shaw, K. A. (2023, March 24). Prevalence and characteristics of Autism Spectrum Disorder among children aged 8 years- Autism and Developmental Disabilities Monitoring Network, 11 sites, United States, 2020. Centers for Disease Control and Prevention. https://www.cdc.gov/mmwr/volumes/72/ss/ss7202a1.htm?s_cid=ss7202a1_w

Podgórska-Bednarz, J., & Perenc, L. (2021). Hyperbaric oxygen therapy for children and youth with autism spectrum disorder: A review. Brain Sciences, 11(916), 1-10. https://doi.org/10.3390/brainsci11070916

Rose, S., Niyazov, D. M., Rossignol, D. A., Goldenthal, M.; Kahler, S. G., Frye, R. E. (2018). Clinical and molecular characteristics of mitochondrial dysfunction in autism spectrum disorder. Molecular Diagnosis & Therapy, 22, 571–593. https://doi.org/10.1007/s40291-018-0352-x

Rossignol, D. A. & Frye, R. E. (2012). A review of research trends in physiological abnormalities in autism spectrum disorders: Immune dysregulation, inflammation, oxidative stress, mitochondrial dysfunction and environmental toxicant exposures. Molecular Psychiatry 17, 389–401. https://doi.org/10.1038/mp.2011.165

Rossignol, D. A., & Rossignol, L. W. (2006). Hyperbaric oxygen therapy may improve symptoms of autistic children. Medical Hypotheses, 67, 216-228. https://doi.org/10.1016/j.mehy.2006.02.009

Rossignol, D. A. (2007). Hyperbaric oxygen therapy might improve certain pathophysiological findings in autism. Medical Hypotheses, 68(6), 1208–1227. https://doi.org/10.1016/j.mehy.2006.09.064

Smith, I. M., & MacDonald, N. E. (2017). Countering evidence denial and the promotion of pseudoscience in autism spectrum disorder. Autism Research: Official Journal of the International Society for Autism Research, 10(8), 1334-1337. https://doi.org/10.1002/aur.1810

The University of Kansas Health System. (n.d.). Hyperbaric oxygen therapy. https://www.kansashealthsystem.com/care/treatments/hyperbaric-oxygen-therapy

Undersea and Hyperbaric Medical Society. (n.d.). Indications for hyperbaric oxygen therapy. https://www.uhms.org/resources/hbo-indications.html

U.S. Food and Drug Administration. (2021, July 26). Hyperbaric oxygen therapy: Get the facts. https://www.fda.gov/consumers/consumer-updates/hyperbaric-oxygen-therapy-get-facts

Zhukova, M. A., Talantseva, O. I., Logvinenko, T. I., Titova, O. S.,  & Grigorenko, E. L. (2020). Complementary and alternative treatments for autism spectrum disorders: A review for parents and clinicians. Clinical Psychology and Special Education, 9(3), 142-173. https://doi.org/10.17759/cpse.2020090310

Citation for this article:

Roberts, B., Leslie, S. C., & Zane, T. (2024). Hyperbaric oxygen therapy: Is there science behind that? Science in Autism Treatment, 21(1).

Other Is There Science Behind That Articles?

Related Research Synopses:

Related ASAT articles:

 

#Researchers #SavvyConsumer

 

Print Friendly, PDF & Email