I think this result has value. It shows up the completely vacuous uselessness of these questionaires so much used by the BPS brigade.
Is this research of value in that it has found something that did not seem to make the participants worse on objective measures?
I think the result doesn't tell us anything much on its own (i.e. that the questionnaires have incorrectly identified improvement, or that no change in the objective measures suggests no harm was done). This is for the reason that Trish noted above; we don't know how useful the chosen objective markers are in measuring improvement or declining health.
Really, every study with interventions aiming to improve ME/CFS should involve the use of personal activity monitors.
I haven't looked at the study properly - here are just some things that jumped out:
this study said:
Therefore, we first assessed the effect of a single session of seated isometric yoga (short-term effect) on several blood biomarkers and autonomic function. We found that a single session of seated isometric yoga with a yoga instructor resulted in beneficial changes, i.e. increases in the serum DHEA-S level and the high frequency (HF) component of HRV, and decreases in HR, serum cortisol, and TNF-α levels. All of these changes shifted the abnormal parameters of the CFS patients closer to those of healthy subjects
We've discussed these yoga experiments before. The fact that someone with ME turns up for the first time to a yoga class with elevated cortisol and an increased heart rate is not surprising - the whole job of getting to the clinic is a major effort. That these markers normalise after a class of what sounded like particularly gentle relaxing seated yoga is not surprising.
this study said:
In contrast, patients in the control group only filled out self-rating questionnaires and did not have blood drawn or do autonomic function tests. This was partly to minimize their physical discomfort, as some patients showed evident allodynia and even the placement of the sphygmomanometer cuff caused substantial pain.
I don't think we picked up this point from the last study though - if you are a patient waiting to have blood drawn, especially when the patient before you is having a hard time with it, that might well have an effect on cortisol and heart rate.
I thought this table was interesting - reference value range; and the plasma biomarkers before and after the intervention. Have a look at the TGF-B1, BDNF and a-MSH values against the reference ranges. Mean BDNF and a-MSH actually departed further from the reference range over the two months of yoga classes (although the change wasn't statistically significant).
this study said:
Pearson’s bivariate correlation analysis showed that the change in the Chalder FS score (mean: − 6.7 ± 6.9) was not correlated with the change in the HADS-D score
This too was interesting. The people who reported an improvement in fatigue (as measured by the Chalder scale) didn't necessarily report an improvement in depression (as measured by the HADS-D tool).
This was annoying:
this study said:
This study also demonstrated that changes in the Chalder FS score were associated with changes in the TAS-20 score, suggesting that a longitudinal improvement in fatigue is associated with reduced alexithymia. A previous study reported higher TAS-20 scores for patients with CFS than for healthy subjects [
24]. In accordance with this study, the TAS-20 score of patients with CFS (55 ± 13) in this study was higher than of a healthy Japanese sample (48 ± 9) [
74]. To date, the pathophysiological significance of alexithymia in CFS is not fully understood.
...
Based on these findings, future treatment of alexithymia might provide a possible strategy for treating CFS
The CFS mean score of 55 for alexithymia is higher than the average (given here as 48) but lower than the 61 required to conclude that someone has difficulty recognising their emotions. It would be good to look into the TAS-20 test to see if chronic illness can affect it. There are only 20 questions, so you'd only need to skew a few questions to change the mean significantly. Another study reported that people with chronic diseases are more alexithymic (worse at identifying their emotions):
another study said:
Patients with chronic diseases are more alexithymic than healthy people. In our research alexithymia has been confirmed in patients with cancer, rheumatoid arthritis and dialyzed patients as well as in patients after myocardial infarction. An alexithymia construct can influence the prognosis and outcome of the chronic disease.
In the online test for alexithymia I just did, there were questions about how I think about the future. I don't know if those are in the TAS-20 but, if they are, then it suggests that there's a problem with the TAS-20 in cohorts with chronic disease - because of course how you think about the future is different. If we haven't already, we should pull apart the TAS-20 sometime.
I could go on, I haven't even got started about my ongoing issues with commentaries about cortisol in ME/CFS.
