Key Takeaway
HBOT shows therapeutic potential for neurodegenerative diseases like Alzheimer's and Parkinson's by reducing neuroinflammation, oxidative stress, and mitochondrial dysfunction.
Summary
This narrative review examined the evidence and mechanistic rationale for using hyperbaric oxygen therapy in neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, vascular dementia, and amyotrophic lateral sclerosis (ALS). The authors synthesized preclinical and clinical findings to evaluate HBOT's potential as a neuroprotective intervention.
The review highlighted several key mechanisms by which HBOT may combat neurodegeneration. Increased oxygen delivery enhances mitochondrial function and ATP production in oxygen-deprived neural tissue. HBOT also modulates neuroinflammatory pathways, reducing pro-inflammatory cytokines and microglial activation that contribute to disease progression. Additionally, the hyperoxia-hypoxia paradox triggers upregulation of antioxidant defenses and growth factors including BDNF and VEGF, which support neuronal survival and angiogenesis.
Preclinical studies in animal models of Alzheimer's showed reduced amyloid-beta plaque burden and improved spatial memory following HBOT. Parkinson's models demonstrated preservation of dopaminergic neurons and motor function. Clinical evidence, while limited, included small trials showing cognitive improvements in Alzheimer's patients and symptom stabilization in Parkinson's patients. The authors concluded that HBOT holds meaningful promise as an adjunct therapy for neurodegeneration but emphasized the need for large-scale randomized controlled trials to establish efficacy, optimal dosing, and long-term safety.
Methods
Narrative review of published literature on HBOT for neurodegenerative diseases. Sources included PubMed-indexed preclinical studies (animal models of Alzheimer's, Parkinson's, ALS, and vascular dementia) and available clinical trials or case series. The review organized findings by disease type and underlying mechanism (oxidative stress, neuroinflammation, mitochondrial dysfunction, angiogenesis).
Key Results
- Preclinical Alzheimer's models: HBOT reduced amyloid-beta plaque accumulation and improved spatial memory in transgenic mice
- Preclinical Parkinson's models: HBOT preserved dopaminergic neurons in the substantia nigra and improved motor outcomes
- HBOT reduced neuroinflammatory markers (TNF-alpha, IL-1beta, IL-6) in multiple animal models
- Enhanced mitochondrial function and ATP production in neural tissue under HBOT
- Upregulation of BDNF and VEGF, supporting neuroplasticity and new blood vessel formation
- Limited clinical evidence: small trials reported improved MMSE scores in Alzheimer's patients and symptom stabilization in Parkinson's patients
- The hyperoxia-hypoxia paradox was identified as a central mechanism driving neuroprotective effects
Limitations
- Most evidence is preclinical (animal models), with limited human clinical data
- Clinical studies had very small sample sizes and lacked rigorous control groups
- Optimal HBOT parameters (pressure, duration, frequency) for neurodegeneration remain undefined
- Long-term effects and safety of repeated HBOT courses in elderly patients are not well characterized
- Translation from animal models to human neurodegenerative diseases is uncertain
- Narrative review format without systematic search methodology or quality assessment