Restless Legs Syndrome (RLS) Discussion Board

A recent study showed that using cool dialysate seems to reduce the severity of WED/RLS in patients on hemodialysis. http://www.ijnmrjournal.net/article.asp ... st=Kashani

From the abstract:

... The aim of this study was to assess the effect of cool dialysate on RLS in hemodialysis patients.

Materials and Methods:... 63 hemodialysis patients were recruited and participated in this clinical trial. The patients were randomly assigned to the intervention group (n = 32) and the control group (n = 31). The intervention group received 35.5°C dialysate and the control group received 37°C dialysate three times a week for a period of 1 month. ...

Results: ... After the intervention, the mean (SD) of RLS severity in the control group was 28.77 (5.45) and in the intervention group was 11.66 (4.69), in which t test showed a significant difference between two groups (t = 14.03, p= 0.001).

Conclusions: Using cool dialysate as a nonpharmacological treatment may reduce the severity of RLS in patients on hemodialysis. Therefore, using this method to improve RLS in hemodialysis patients is recommended.

What the heck? Do they have any idea why?

What the heck? Do they have any idea why?

They offer a number of suggestions, but they don't know why.

I think people have been using cool dialysate to prevent blood pressure and other circulatory problems, and they noticed that it seemed to reduce WED symptoms, which led them to do a proper study on it. I didn't actually read the paper, it's not written in a way that I admire, but your question prompted me to at least see if I could find out if they had a hypothesis as to why it worked.

They say that patients on hemodialysis experience a rise in body temperature during the session, because the body's ability to lose heat becomes impaired. This heating causes dilation of central blood vessels and consequent reduced cardiac output, and a slew of other bad things, and, especially when combined with the fluid loss during dialysis, causes contraction of ?? blood vessels - do they mean peripheral blood vessels? OK they lost me there.

They offer a number of suggestions as to why cool dialysate would reduce WED symptoms:

• - It seems that increased beta-endorphins have been noted in non-WED/RLS patients after 4 hours of cool dialysis, and since beta-endorphins reduce WED/RLS symptoms, they suggest that this might be the mechanism by which WED/RLS patients benefitted.
• - Also, cool dialysate decreases "hypoxia levels " (where?); we know that peripheral hypoxia may be involved in WED/RLS.
• - Or maybe (they suggest), cool dialysate decreases the function of sensory receptors and that helps somehow (like an anesthetic).
• - Or the benefit arises because cold temperatures reduce the amplitude and frequency of impulses arriving at nerve endings, reducing the perception of pain/discomfort.
• - Or the cold modulates spinal cord excitability; it is thought that spinal cord excitability is involved in WED/RLS.

Interesting quote, especially for polar bear:

Happe et al. showed reduction of
the local and whole body temperature with cryotherapy has
been successful in reducing RLS symptoms. They observed
that local cryotherapy was less effective than whole body
cooling[23] which is in line with the results of the recent
study.

23: Happe S, Evers S, Thiedemann C, Bunten S, Siegert R.
Whole body and local cryotherapy in restless legs syndrome:
A randomized, single‑blind, controlled parallel group pilot study.
J Neurol Sci 2016;370:7‑12.
Have we seen that one before? I don't recall it. I will have to dig it up!

Thanks, Beth . I usually read the board right before bed when the meds are working and when I am in NO shape to read anything, lol. You saved me!

A great explanation Beth.