I know what OP is concerned about. I don’t know how true the problem is, and in which states, but . . .
There are horror stories galore out there. I’ve heard a few second-hand.
Some states (e.g., California) require certain doctors or similar health-care professionals to report certain medical conditions to the state – including certain conditions to the DMV that might impair a driver’s ability to drive. (Uncontrolled epilepsy being one of them.) So much for HIPAA protections. What, you thought HIPAA protections went so far as to protect you from government snooping into your medical status?
The problem is – according to the rampant horror stories – that the DMV is waaaaaaay to quick to strip you of your driver’s license, immediately and without necessarily much if any notice – upon the flimsiest reports from your doctor. You are totally at the mercy of your doctor here. You have no recourse against your doctor if you think his diagnosis is wrong, or if you think he’s retaliating against you for refusing to take that test he suggested, or whatever. By law, your doctor is immunized against any kind of legal action for whatever he reports. Doctors are under pressure, by law, to report because they can get in trouble if they don’t – so they have incentive to err, if at all, on the side of reporting you even in questionable or borderline cases.
On the other hand, the DMV makes it waaaaaaaaaay to difficult for you to get your license back. You can appeal to the DMV, wait four to six months for a hearing (for which you must pay a $400 fee, as I heard it told). Hopefully, they will schedule a hearing at some location you can get to, inasmuch as you are NOT allowed to drive yourself there – you need someone to drive you (or maybe take public transportation). And it’s still a crap-shoot if you’ll ever get your license back.
Now, I myself don’t know how much of any of the above is actually true. I do know that there are horror stories out there.