Given the statements made in the article, it would seem rather straightforward to look at the incidence of ADRD in the population of existing carvedilol patient

Given the statements made in the article, it would seem rather straightforward to look at the incidence of ADRD in the population of existing carvedilol patients. I would think such a thing would precede even a model study, and it's interesting there was no mention of such research. Knowing basically nothing of how such data might be collected or kept, is this trivial or stupidly difficult?