How can you tell if orthostatic hypotension is Neuro or Non Neuro?

I have orthostatic hypotension, but not every time I stand up. Sometimes I stand up and it goes from 100/70 to 150/100 within 3 minutes. Having a tilt table off in the future, but I would like to understand how you know if it’s from your brain. I also have post meal b/p drop every time I eat. TIA