Hyperbaric Oxygen Therapy Upregulates Neurotrophic Factors to Ameliorate Post-Stroke Depression: A Randomized...

Post-stroke depression (PSD) affects 29-52% of stroke survivors, with inflammation as a key pathophysiological mechanism. Hyperbaric oxygen therapy (HBOT) may modulate neurorestoration, but clinical evidence is limited. While meta-analytic evidence suggests HBOT may benefit PSD symptoms, high-quality randomized controlled trials employing rigorous sham-control and concurrently investigating neurotrophic mechanisms remain scarce.

In this randomized, double-blind, sham-controlled trial, 61 PSD patients were allocated to HBOT (n=29) or Sham-HBOT (n=32) groups, respectively. HAMD, NIHSS and MBI scores and serum Brain-Derived Neurotrophic Factor (BDNF), and beta-Nerve Growth Factor (beta-NGF), were evaluated at baseline as well as 2 and 4 weeks after HBOT intervention. The primary outcome was the change in the 17-item Hamilton Depression Rating Scale (HAMD-17) score from baseline to week 4, analyzed in the modified intention-to-treat population. The trial was registered (ChiCTR2100053522).

HAMD scores decreased significantly in the HBOT group vs sham-group at weeks 2 (p=0.017) and 4 (p<0.01). Serum BDNF and beta-NGF, levels were significantly elevated in the HBOT group (all p<0.01). Reductions in HAMD scores correlated with increases in BDNF (r = 0.66, p < 0.05) and beta-NGF (r = 0.47, p =0.01). HAMD scores decreased significantly in the HBOT group compared to the sham-group, with the between-group difference reaching significance at week 2 (p=0.017) and week 4 (p<0.001). Exploratory subgroup analyses by stroke type (ischemic vs hemorrhagic) and age (dichotomized at the median of 65 years) were conducted and these analyses revealed no significant interaction between treatment group and either stroke subtype or age subgroup on the change in HAMD-17 scores (all p > 0.05), suggesting a consistent trend of HBOT effect across these subgroups within this limited sample.

This preliminary trial suggests that a 4-week course of HBOT may alleviate depressive symptoms in PSD patients, an effect associated with increased serum BDNF and β-NGF levels. Given the limited sample size and short follow-up, its long-term efficacy and clinical positioning require validation in larger trials with extended follow-up.