How to diagnose the initial stage of Alzheimer’s disease? Are there any external signs of an impending disease?

Cloudy crystalline lens - cloudy eyes of obscure tones sometimes indicate the onset of atherosclerosis, which is very often the beginning of Alzheimer’s disease. Deafness and deafness that are not associated with hearing loss may also be a signal of changes in the brain and the onset of the disease. Memory impairment - a person may forget what they did 10 minutes ago. Focusing on an action - A person seems to be hovering on something, for example, opening a book and spending hours ““reading”” the same page. Bad recognition of people, often even relatives - a person behaves with them as a stranger, unmotivated aggression towards them. Passivity to what is happening - the person does not care about anything that is happening to others or to himself.  At least my father had such signs, even specialists from https://www.startstemcells.com/ confirmed his diagnosis. Now, let’s treat it, it’s okay.