Hyperbaric oxygen could improve symptoms in patients with “long COVID”
In a randomized trial, 8 weeks of treatment was associated with improvements in cognition, mood, fatigue, and pain.
Hyperbaric oxygen has a checkered history as a therapy for several disorders, due to studies that were small and poorly controlled. A new randomized, double-blind, sham-controlled trial from Israel suggests it could be useful in people with persistent cognitive problems, fatigue, and pain for at least 3 months after acute COVID-19 (i.e., "long COVID").
Hyperbaric oxygen therapy or a sham procedure was administered to 73 long COVID patients for 5 days a week for 8 weeks. Participants were asked to guess whether they had received hyperbaric or sham oxygen therapy: participants in either arm were unable to guess correctly.
Symptom questionnaires, formal cognition tests, and magnetic resonance imaging (MRI) studies of the brain were performed before treatment and 1 to 3 weeks after treatment. Before treatment, the results of these measurements were not different in the two groups. However, after treatment, the hyperbaric oxygen therapy group had significantly better cognitive function, less fatigue, less pain, and fewer complaints of mood disorders than the sham group. In the oxygen group,
This well-controlled report shows objective improvements in the brain that correlate with symptom improvement. For this reason, the report will surely lead other groups to try to confirm these findings. If hyperbaric oxygen therapy is considered effective, the optimal duration of therapy must be defined. It remains to be determined whether the benefit is sufficient to justify the time and expense.
Summary
Post-COVID-19 condition refers to a variety of persistent physical, neurocognitive, and neuropsychological symptoms after SARS-CoV-2 infection. The mechanism may be related to brain tissue pathology caused by virus invasion or indirectly by neuroinflammation and hypercoagulability.
This randomized, sham-controlled, double-blind trial evaluated the effect of hyperbaric oxygen therapy (HBOT or HBO2 therapy) in post-COVID-19 patients with ongoing symptoms for at least 3 months after confirmed infection.
Seventy-three patients were randomized to receive 40 daily sessions of HBOT (n = 37) or sham treatment (n = 36). Follow-up assessments were performed at baseline and 1 to 3 weeks after the last treatment session.
After HBOT, there was a significant group by time interaction on global cognitive function, attention, and executive function (d = 0.495, p = 0.038; d = 0.477, p = 0.04 and d = 0.463, p = 0.05 respectively).
A significant improvement was also demonstrated in the domain of energy (d = 0.522, p = 0.029), sleep (d = − 0.48, p = 0.042), psychiatric symptoms (d = 0.636, p = 0.008), and pain interference (d = 0.737). , p = 0.001).
Clinical outcomes were associated with significant improvement in brain MRI perfusion and microstructural changes in the supramarginal gyrus, left supplementary motor area, right insula, left precentral frontal gyrus, right middle frontal gyrus, and superior corona radiata. .
There were no significant differences in any of the reported side effects between the groups (35.1% and 38.9%, p = 0.739 in the HBOT and control groups, respectively). None of the patients needed to stop treatment due to side effects.
These results indicate that HBOT can induce neuroplasticity and improve cognitive, psychiatric, fatigue, sleep, and pain symptoms in patients suffering from a post-COVID-19 condition.
Discussion
This is the first prospective, randomized, sham-controlled trial to demonstrate significant improvement beyond the expected clinical recovery course of the post-COVID-19 condition. We found that HBOT improves dysexecutive functions, psychiatric symptoms (depression, anxiety and somatization), pain interference symptoms and fatigue. These changes were associated with increased CBF and brain microstructural changes in frontal, parietal, and limbic regions associated with cognitive and psychiatric functions.
Becker et al. show that the main cognitive impairment in the post-COVID-19 condition is dysexecutive or brain fog, with considerable implications for occupational, psychological and functional outcomes. In this study, improvements in the memory domain were found in both groups, which may be attributed to the natural course of the disease. However, executive function and attention improved only after HBOT.
In conclusion , HBOT can improve dysexecutive functions, psychiatric symptoms (depression, anxiety and somatization), pain interference symptoms and fatigue of patients suffering from a post-COVID-19 condition. The beneficial effect can be attributed to increased brain perfusion and neuroplasticity in regions associated with cognitive and emotional functions. Further studies are needed to optimize patient selection and evaluate long-term outcomes.
