Trial Report Ten sessions of hyperbaric oxygen versus sham treatment in patients with long covid HOT-LoCO…, 2025, Kjellberg et al.

Great to see a good quality trial, even if it has a null result.
Karolinska University, Sweden.
Adequately sized trial

I guess it is always possible to say 'ah, but the treatment should have been slightly different' - given for longer, given at a higher dose, given by better trained therapists... But still, this is useful.

That's an interesting organisation - International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human use-Good Clinical Practice - website here: https://www.ich.org/

 

Great to see this. I'm assuming this is a good association?

The following is a lot, but it looks as though they have really tried hard to reduce bias and do things well. They also paid a lot of attention to blinding.

Inclusion criteria are basically healthy and working/studying prior to Covid-19 infection, persisting symptoms post-Covid-19 infection for at least 12 weeks and ongoing, diagnosed with a post-covid-19 condition. The people included were mostly fairly young, healthy BMI.

 

Change in SF-36 Physical Function
(note, SF-36 Physical Function is the 10 questions about things like whether you can walk a block or a mile, or climb a flight of stairs or 3, or have trouble bathing and dressing. RP is Role Physical - 4 questions asking things like 'were you limited in the work or activities you could do due to your physical health?'.

I wanted to highlight this. Higher scores mean better physical health. These people were scoring in the 0 to 50 range, which is low compared to the general population, but, I think, in line with what people with an ME/CFS-type illness participating in a trial would report.

The mean improvement was an increase of around 9 on the 0-100 scale from a baseline score of about 38. That's a pretty substantial improvement in percentage terms, nearly 25%. And that is from both a convincing placebo and from a treatment that turned out to be no better than a placebo that I expect most of the participants would have been very hopeful about. The treatment did not involve instruction in the benefits of ignoring symptoms, thinking positively or reframing symptoms as benign, nor did it specifically encourage people to increase their physical activity.

 

Sad to see that the death in the placebo group was from a suspected suicide.

The authors still seem very hopeful that tweaking the treatment offering will produce a useful result.