This article is part of the HBOT Radar series, where we summarize the latest published hyperbaric oxygen therapy research.
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Disclaimer: This article is intended for educational and informational purposes only. It summarizes published medical research conducted in clinical settings and does not evaluate Brain Spa Hyperbaric products. The hyperbaric chambers offered on this website are non-medical wellness devices and are not intended to diagnose, treat, cure, or prevent any disease. Do not make medical decisions based on this article — consult a qualified healthcare professional.
📌 395 People. Three Different Conditions. One Shared Result: Better Sleep.
🔍 What this study explored
Everyone wants to sleep better. But "sleep better" means different things to different people — and different conditions wreck your sleep in different ways.
If you're aging, your sleep fragments. You wake up more often, spend less time in deep sleep, and your circadian rhythms drift. If you're dealing with long COVID, fatigue and brain fog blur the line between exhaustion and insomnia — you're tired but can't sleep well. And if you have PTSD, sleep becomes a war zone: nightmares, hypervigilance, an inability to let your guard down enough to fall asleep.
So when researchers at the Sagol Center for Hyperbaric Medicine and Research in Israel — the same group behind some of the most cited hyperbaric oxygen therapy research — decided to study HBOT's effect on sleep, they didn't pick just one population. They looked at all three. And with 395 patients, this is the largest HBOT sleep study ever conducted.
The question they asked was elegantly simple: does HBOT improve sleep regardless of why your sleep is broken?
🌬️ HBOT protocol used in this study
- Design: Retrospective longitudinal study
- Patients: 395 adults (mean age 57.9 years, 31% female)
- Healthy aging: 180 patients (age 50+, no neurodegeneration, living independently)
- Long COVID: 92 patients (persistent cognitive symptoms 3+ months after infection)
- PTSD: 123 patients (clinical diagnosis, treatment-resistant, still symptomatic)
- Protocol: 60 sessions of HBOT at 2.0 ATA, breathing 100% oxygen, 90 minutes per session, 5 days per week, with periodic air breaks. Conducted in a multiplace hyperbaric chamber.
- Outcome measure: Pittsburgh Sleep Quality Index (PSQI) — a validated 21-point questionnaire covering seven components: subjective quality, latency (time to fall asleep), duration, efficiency, disturbances, medication use, and daytime dysfunction. Higher scores = worse sleep. Score above 5 = clinically disturbed sleep.
This study was conducted in a clinical hospital setting under medical supervision. Results from clinical research cannot be directly applied to other settings or devices — always consult a healthcare professional.
📊 Key findings
Sleep improved in every group — significantly
After 60 HBOT sessions, total PSQI scores dropped significantly across the board:
| Group | Before HBOT | After HBOT | p-value | Effect size |
|---|---|---|---|---|
| All patients | 9.0 ± 4.0 | 8.2 ± 3.8 | p < 0.001 | Cohen's d = 0.91 |
| Healthy aging | 7.1 ± 3.3 | 6.5 ± 3.0 | p < 0.001 | Cohen's d = 0.37 |
| Long COVID | 8.4 ± 3.6 | 7.7 ± 3.3 | p < 0.001 | Cohen's d = 0.54 |
| PTSD | 12.1 ± 3.5 | 10.9 ± 3.6 | p < 0.001 | Cohen's d = 0.74 |
PTSD patients started with the worst sleep (12.1 — severely disturbed) and showed the largest absolute improvement. But all three groups improved significantly.
The worse your sleep was, the more HBOT helped
This is one of the most useful findings. Regression analysis showed that baseline PSQI was the single strongest predictor of improvement (B = 0.494, p < 0.001, r = 0.46). In plain language: the worse your sleep was before treatment, the more it improved afterward.
When the researchers excluded people who already slept well (PSQI ≤ 5) and looked only at the 332 patients with genuinely disturbed sleep, the improvements were even more pronounced — overall PSQI dropped from 10.76 to 8.82 (p < 0.001), with significant gains in sleep disturbances, latency, subjective quality, duration, and daytime dysfunction.
Normal sleepers? Minimal change. Which makes biological sense — if your sleep isn't broken, there's not much to fix.
What specifically improved — and what didn't
Three components improved significantly in all three groups:
- Subjective sleep quality — people felt they slept better
- Sleep latency — they fell asleep faster
- Sleep disturbances — fewer wake-ups and disruptions
Daytime dysfunction (feeling impaired during the day) improved in aging and long COVID groups, but not in PTSD — which the authors note may reflect the broader symptom burden of PTSD that goes beyond sleep.
Two things that did NOT change: sleep medication use (patients didn't reduce their pills) and sleep efficiency (time in bed vs time asleep). This suggests HBOT doesn't replace medication — it adds to whatever medication is already doing.
🧠 Why this matters
The cross-population finding is the key insight here. Sleep is disrupted by aging through one set of mechanisms (circadian drift, neurodegeneration). By long COVID through another (neuroinflammation, autonomic dysregulation). By PTSD through yet another (hyperarousal, nightmare-driven fragmentation). The fact that HBOT improved sleep in all three suggests it may work through a mechanism upstream of all of them — something fundamental about how oxygen affects the brain.
The researchers propose several pathways: HBOT is known to reduce neuroinflammation, improve mitochondrial function (which has been linked to sleep regulation), promote angiogenesis in the brain, and enhance neuroplasticity. These are broad mechanisms that could influence sleep regardless of what's disrupting it.
There's also an intriguing dose connection. The study explicitly references the HOT-LoCO trial (which we recently covered), noting that 10 HBOT sessions didn't improve sleep in long COVID patients — but in this study, 60 sessions at a similar pressure did. This reinforces the emerging consensus that HBOT's neuroplastic effects require a cumulative dose to take hold.
The honest caveats:
- Retrospective, no control group. This is the big one. Without a sham group, we can't know how much improvement came from HBOT versus the passage of time, the attention of medical staff, or placebo effects. The authors acknowledge this clearly.
- Subjective outcome only. PSQI is a questionnaire — it measures how people perceive their sleep, not objective sleep physiology. No polysomnography, no actigraphy. People might feel they sleep better without actually sleeping differently.
- Sagol Center / Efrati group. This is the world's most prolific HBOT research group and is commercially connected to HBOT through AVIV Scientific. Their work is consistently peer-reviewed and high-quality, but the commercial interest warrants transparency.
- 60 sessions is a substantial commitment. That's 12 weeks of daily treatments — a significant investment of time and money. Whether more accessible protocols (fewer sessions, lower pressure) could achieve similar sleep benefits is unknown.
- Selection bias. Only patients who completed all 60 sessions and filled out questionnaires were included. Those who dropped out or didn't complete questionnaires may have had different experiences.
📌 Takeaway for the community
- The largest HBOT sleep study ever conducted (395 patients) found significant sleep improvements across three different populations — healthy aging, long COVID, and PTSD
- The worse your baseline sleep, the more improvement HBOT was associated with — people who already slept well saw minimal change
- Sleep quality, time to fall asleep, and overnight disturbances all improved in every group; medication use didn't change
- The cross-population finding suggests HBOT may improve sleep through fundamental brain mechanisms rather than condition-specific pathways
- Without a control group, these are associations — not proof of causation. The authors call for controlled trials with objective sleep measurements
- All patients received 60 sessions at 2.0 ATA — this study was conducted in a clinical hospital setting under medical supervision
Source: https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2026.1690633/full
Doenyas-Barak K, Elman Shina K, Lang E, Finci S, Elkarif V, Shorer R, Efrati S. The effect of hyperbaric oxygen therapy on sleep quality across diverse patient populations. Front Neurol. 2026;17:1690633. doi: 10.3389/fneur.2026.1690633.
Educational disclaimer
This content summarizes findings from published medical research for educational purposes only.
The hyperbaric chambers sold on this website are non-medical wellness devices and are not intended to diagnose, treat, cure, or prevent any disease.
The studies discussed here were conducted in clinical medical settings using medical-grade interventions. The inclusion of research summaries does not imply that similar outcomes can be achieved using non-medical wellness devices.
