Paula, How utterly rude the behavior of the clerk--and you are correct, he probably knew less than you about PD and coQ10, and did not want you to know that, thus the delay until you left.
My bias is that a fat soluble statin was responsible for the onset of my husband's PD--whether it "unmasked" the disease or directly caused it, I am not certain (how can one be??). Statins interrupt the pathway to production of coenzyme Q10--this isoprenoid shares the same pathway as that leading to cholesterolgenesis. There are several other "pleiotropic" effects of statins that may also be responsible, but depleting the body of one of the metabolites found to be depressed in all PD patients irregardless of their statin status, seemed a good place to begin. Thus the decision to begin CoQ10. At that point, coq10 was the only anti PD drug my husband was taking, and this was even before his diagnosis, thus early in the disease. The response was a very positive one--though was quickly followed by use of other vitamins and minerals as well as supplements focused to replace what statins had depleted/interferred with. The first anti PD drug my husband began was Azilect, about 3 months after beginning coQ10., though his initial symptoms were much reduced prior to taking Azilect. Amantadine was added sometime later. I have not followed the Phase II trials very closely, since I ascribe to the belief "if it ain't broke, don't fix it"--since coQ10 helps my husband, he will continue with it until he feels it has no benefit. I do know there were mega dose coQ10 clinical trials slated for ALS, Alzheimer's and huntington's. Seems a couple of those were dropped for lack of efficacy, though again, I have not followed those trials.
As for the increase in symptoms if he forgets to take coQ10, I do not know if the prior statin use accounts for this or not. Again, I feel "parkinson's disease" is not one disease entity but a constellation of different disease states, with many different etiologies. Thus what one person responds to, another may not. Maybe it would be more correct to label these "parkinsonism" instead of "parkinson's disease". Would be interesting to know if any others who respond positively to coQ10 also took/take a statin. I do not have an opinion as to whether coQ10 should help you at this stage. It is expensive--though if you belong to Sam's or know someone who does, their product is supposed to be quite good and not as expensive. Wish this stuff was more definitive; living with the disease is enough without feeling one must also guess what will help! madelyn