In many cases, mild cognitive impairment is found to be caused by something completely aside from Alzheimer’s, such as obstructive sleep apnea or memory-hurting medications, depression or other disorders like Parkinson’s disease. Vascular problems such as undetected strokes can be a cause, as can a vitamin B-12 deficiency or mood disorders.

KANSAS CITY, Mo. — For people of a certain age, it takes only a few “senior moments” — struggling for words, names or memories — to cause worry.

Is this normal aging or mild cognitive impairment (MCI)? Is it all a run-up to Alzheimer’s?