Experiencing excessive daytime sleepiness as an older adult can spell dire consequences that ultimately may lead to full-blown dementia, according to a new study funded by the National Institute on Aging.

People with the syndrome walk slowly and report memory problems, but they do not have a mobility handicap or dementia. Motoric cognitive risk syndrome is a condition that can develop before dementia.

Predementia is a term used to describe the cognitive impairment symptoms in the early stages of Alzheimer's disease.