In CAH the adrenal glands work, but produce the wrong stuff, therefore the chemical feedback is continually demanudng for more of what it’s supposed to produce, makeing it work hard and get larger (HYPER, meaning more or bigger--thus Congenital Adrenal Hyperplasia). With the meds, though the proper hormones are present, the feedback loop is satisfied and the message to work isn’t sent (or not sent very often) and the adrenal gland getsmaller, from what I understand smaller than healthy adrenal glands.

What they’ve found with steroids in sports is that while the added steroids produced the muscle growth, after prolonged use it caused the testes to atrophy from lack of use. Not a desirable side affect.

If something is interfering with the body/mind’s instructions to produce adrenaline, then the adrenal medulla would eventually respond by atrophying, just as the adrenal cortex does to maintenence hormones for CAH and the testes do in response to over use of anabolic steroids. So the physical condition of the adrenal medulla could be an effect from an outside cause, not a cause itself.