Preprint cerebral blood flow relation is abnormal in most ME/CFS patients with a normal heart rate and blood pressure response, 2024, van Campen et al

I just want to mention that based on my personal experience (very severe OI), knee-high compression socks (class II, 23-32 mmHg) is enough to make a noticeable and useful difference, measurable by the blood pressure monitor as well. Thigh-highs are more effective, but the knee-highs really do help enough to be of actual use.

I have tried high-waisted compression tights too, as well as regular firm control "shapewear" for example very high-waisted shorts. Personally I find all these a bit too uncomfortable and restricting to wear on a daily basis. In my case they haven't made much of a difference compared to the thigh-highs.

@Jonathan Edwards Sorry if you find my repeated comments on this topic annoying

 

Perhaps salt water has a longer lasting effect than predicted for this reason:

My orthostatic symptoms are dependent on how long I've been upright and the type of stressor. Sitting is better than standing but worse than lying down. Riding a bike is better than walking. Standing is worse than walking. The worst thing is repeatedly alternating between squatting and standing.

The stress caused by this accumulates over the course of the day. Drinking salt water, even just once, may lead to a lower overall stress level at the end of the day even if by then blood volume is not different.

The best thing is to repeatedly drink salt water.

 

Yes, things may be pretty complicated over a longer period of say hours. And it may vary from person to person depending on whether they have a tendency to develop oedema, like my left leg and maybe @mango?, or maybe widened calf veins.

So it would be useful to have some proper measurements from a study.

 

Salt helps my OI, too, and generally makes me feel less unwell. I used to add a bit to food, till I stayed with someone who didn't use salt in their cooking and realised my muscles weren't on fire any more. It's so painful that OI's the lesser evil.

Next best is leg compression. It doesn't resolve the low-grade headache as completely as salt, but it does improve it—when the weather's cooled down enough to wear compression garments again, my head clears within seconds. It's one of those grumbling background things that's most obvious when it stops.

 

Why not start with a trial to measure blood volume ? Was this ever discussed at the research working group @Jonathan Edwards

 

No it wasn't, but I think measuring blood volume is not that simple. It also isn't necessarily what we really want to know - which is perfusion flow in specific organs. The relation to volume may be complicated.