Plasma Exchange

#21

I took another look at the study and noticed that

Surprisingly, we observed no significant BA differences at time point 3 compared to sham in any group, suggesting potential compensatory mechanisms that mitigate the anti-aging effects after multiple sessions

Afaict, they took samples before session 1, 4 and 6, corresponding to time points 1, 2 and 3. The quote above indicates there is actually no benefit to TPE, or at least, you want to stop after 3 sessions. I wonder if this is a limitation of the sample size or if it truly indicates a null result here. IMO the study is written in a way that makes it sound better than it actually is by consistently referring to the benefits at time point 2, despite the end result being no better than sham. I suppose saying it didn’t work by the end of the study only takes one sentence so that’s what they put (as quoted above).

I think they really should have taken samples at least a month after the final session, I’m actually a bit perplexed as to why they would go through all of this effort and cost without doing some, presumably relatively cheaper, final testing. I also don’t understand why they did the 6th session at all if they only took samples before the 6th session (for time point 3). Perhaps I’m missing something here?

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#22

Here’s an interesting small study done on plasma donation comparing the results to TPE

Takeaways:

  1. Frequent plasma donation may have similar results to TPE, at least for some proteins, but not all.
  2. Circadian variation of the proteomics has a large impact on the results. Studies must control for the time of day that blood is drawn for testing.
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#23

Post them when you get them.

#25

“The quote above indicates there is actually no benefit to TPE, or at least, you want to stop after 3 sessions. I wonder if this is a limitation of the sample size or if it truly indicates a null result here”.

It appears Kiprov et al believe that a null result is indicated, by the pain they do take to make an explanation: (“restoring” is ingenious instead of “nullify”)

“We find that the subsequent therapy sessions restored most of the benefits of the first three sessions, with the restoration being linearly dependent on the initial BA (biological aging) effects …We postulate that this may be due to either cell-intrinsic programming, in which cells have inherent mechanisms to compensate and adapt to changes induced by the therapy, or exposome effects, in which lifestyle and environmental factors restore the body back to its baseline state, reducing the response to treatment over time”.

The study is a huge disappointment. As I understand it, it’s likely a nail in the coffin for TPE.

As quoted by dicarlo2 “no difference in outcome between any of the treatment groups and the sham group between baseline and the last measurements, indicating compensatory mechanisms setting in after the improvements seen in the mid term”.

Another lesson learned: short-term results are no proof. Postive results after three months, none after six months.

#26

Further questions I would have:
is there any publication in a peer review respectable journal that shows a substantial and statistically significant result (p=0,05 or better) for plasma exchange without any simultaneous changes in medication, diet or training effort.
If yes : how much plasma was exchanged volume/exchange and how often.
How long did the result last. If we can find the half-life for the effect we might be able to find which factor in SASP is behind this mechanism (interleukin?, or some other substances washed out)
Hopefully it would result in finding a much simpler way to influence that factor. :slight_smile: