Use of sildenafil (viagra) to alter fatigue, functional status and impaired cerebral blood flow in ... CFS, 2020, Friedman (Pfizer)

This study was double-blinded.



It's a bit odd that the study was finished in 2010, but not written up until 2017.




The reduction in fatigue could be significant e.g. an average reduction of 32 could mean that someone scoring most of the 42 questions as most severe (5 out of 5) at baseline could have improved so that most measures were only 4 out of 5.


But that Primary Outcome Measure looks odd. The sildenafil was taken for 6 weeks, but it says the values are compared at 6 months. That seems unlikely to be correct.

And the scoring looks odd too. 42 questions with a scoring range of 0,1,2,3,4. So the maximum score should be 168. But the study entry says the maximum is 148.

So, it's hard to know what to make of this very small study. It would be interesting to hear from the researcher - was there any followup? And, if not, why not?

 

I emailed Professor Friedman, asking about the trial, including whether the blinding might not have worked, and he very kindly replied:

Which is a shame.

 

Same. But, @Barry, you've made me do it. It actually was even better than that, Professor Friedman is an 'Endowed Professor'.

Maybe the puerile jokes related to being a well-endowed professor studying viagra were part of why the study was more trouble than it was worth.

 

Seriously though, it is a shame the study couldn't be completed properly. I feel fairly sure that problems with blood circulation are part of the ME/CFS pathology.

If the treatment can't be blinded, perhaps there could be some objective outcomes. Activity level might be one, although that would have to be measured for quite a long time to make sure it really was objective - which means treatment for a long time too. Measures of orthostatic intolerance perhaps would be more responsive.

 

Orthostatic intolerance = 'problems being upright'...
A minefield of double entendre.