Survival stress also impacts liver function leading to poor lipid metabolism which in turn can impact cholesterol absorption and lead to cortical thinning. Which is also an effect that we see from methamphetamine use in various animal models, which by it's nature of being controlled trail seems to exclude the stress factor. https://pubmed.ncbi.nlm.nih.gov/28689763/

I would agree with you in general, but there are situations where prescribed methamphetamines also lead to cortical thinning when not used as recreationally. This seems to suggest that stress may not be the entire player here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3870784/

It was likely decided because of the dose of meth found in the persons systems that correlates with various findings on dose-dependence https://jamanetwork.com/journals/jamapsychiatry/fullarticle/...

If you would like to read more about PTSD findings as it relates to stress and liver function, I would be happy to expound upon the way that corticosteroids impact gut bacteria that directly affect FXR metabolism and bile acids and further lead to cortical thinning. https://academic.oup.com/cercor/article/30/2/575/5521088

Its really fascinating how a drug like methamphetamine impact neuroactive steroids that impact the same pathways tha stress does. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6862925/ We've been able to reverse it in rats https://www.sciencedaily.com/releases/2013/10/131007093739.h...