EC Neurology

Traumatic brain injury (TBI) frequently results in persistent autonomic dysregulation, often manifesting as sympathetic dominance and attenuated parasympathetic tone. These maladaptive shifts in autonomic balance are linked to impaired neurovascular coupling, heightened systemic inflammation, and hindered cognitive recovery. In this observational study, we evaluated the physiological effects of a multi-modal therapeutic protocol-comprising mild hyperbaric therapy (MHBT), photobiomodulation (PBM), and molecular hydrogen (MH) therapy-on autonomic nervous system (ANS) function in a clinically diverse TBI cohort.

Using heart rate variability (HRV) as a biomarker of autonomic output, we observed a 17% reduction in low-frequency/high-frequency (LF/HF) ratios, indicative of decreased sympathetic dominance, in a sample of ten patients (mean age: 53.4 ± 8.2 years; 6 males, 4 females).

Subgroup analyses revealed that female and older participants experienced favorable shifts in HRV Total Power and LF/HF ratio, while male and younger participants exhibited less consistent or adverse responses. Mechanistically, this protocol targets mitochondrial, oxidative, and neurovascular pathways implicated in ANS dysfunction post-TBI. These findings underscore the potential relevance of biologically stratified therapeutic strategies in neurorehabilitation.

 Keywords: Traumatic Brain Injury; Autonomic Nervous System; Heart Rate Variability; Multi-Modal Therapy

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