Summary

Background:

Post-traumatic stress disorder (PTSD) remains a significant and often refractory mental health condition. Hyperbaric oxygen (HBO) therapy has demonstrated promise in alleviating symptoms of PTSD but optimal dosing and treatment duration remain unclear.

Objectives:

To evaluate the clinical efficacy and dosing effects of two HBO protocols in patients with PTSD.

Methods:

We conducted a randomized controlled trial comparing two HBO protocols: 60 daily sessions of 90 minutes at either 2.0 atmospheres absolute (ATA) or 2.5 ATA (HBO15). Adults with severe PTSD (Clinician Administered PTSD Score [CAPS]-5 ≥ 33) were randomized to treatment arms. CAPS-5 scores were recorded every 2 weeks. Secondary outcomes include measures of depression, sleep, executive function, and safety. Preliminary results are presented for the first nine patients who completed therapy (HBO10: n=5; HBO15: n=4).

Results:

Participants in HBO15 were younger (mean age 39 vs. 59 years, P = 0.2). Baseline PTSD severity (CAPS-5) was higher in HBO15 (median 61.5 vs. 48.0, P = 0.4). Other baseline psychological scores were similar between groups. Mean CAPS-5 improvement (ΔCAPS) was greater in HBO15 (-14.0 ± 21.2) vs. HBO10 (-5.3 ± 19.6), although not statistically significant (P = 0.8). Both groups demonstrated the largest symptom reduction by weeks 6–8, with a plateau observed thereafter despite continued treatment through week 12.

Conclusions:

Preliminary data suggest both HBO protocols are associated with symptomatic improvement in PTSD, with a trend toward greater effect in the higher-pressure group (2.5 ATA). Improvements appear to peak around 6–8 weeks, potentially indicating a shorter optimal treatment duration.