Hi Colm, and everybody else,
I note that this guy does not mention what symptoms he had, their severity, and their duration in days.
That says, in my own vision of what causes POIS, cortisol do have a role for cluster 3 ( cognitive and other pellagra-like symptoms), and cluster 4 ( emotional symptoms), because cortisol up-regulates the activity of TDO ( Tryptophan 2,3-dioxygenase), one of the two enzymes that hack the tryptophan metabolic pathways toward the kynurenine pathways ( for those interested, look at the diagram attached - on the lower left you will see that cortisol boosts the activity of TDO ). However, in my overall vision of what causes POIS, cortisol has no effect on IDO, the other enzyme that leads to the kynurenine pathways as well, so his explanation cannot be complete.
Moreover, cortisol has nothing to do with cluster 1 symptoms ( allergy-like ) and cluster 2 symptoms ( flu-like ) symptoms. For cluster 1 and 2, I agree with the cytokines production/immune reaction that Dr Waldinger has suggested is at play in POIS. Again, his techniques may have work for him, but based on what I understand, it wouldn't work for all POIS sufferer.
A better, healthier nutrition helped me, and the practice of yoga and meditation, through the years, did help me to have less severe and shorter POIS, and still do help me, but it did not take it all away. The addition of other things, in particular IDO inhibitors like rosemary and curcumin, do help me a lot more still.
As G-men says, this guy may have been a mild case of POIS, but he does not give much details, only that it only has it for 6 months. Getting rid of it after 6 years rather than 6 months would have been more convincing.