Drowsiness, Staring May Signal Alzheimer’s
Study: Staring Off Into Space, Drowsiness, Other Mental Lapses May Be Early Alzheimer’s Symptoms
WebMD News Archive
Jan. 19, 2010 -- Drowsiness, staring off into space, or losing your train of
thought may be early symptoms of Alzheimer’s disease, according to a new
Researchers found that people with at least three different symptoms of
mental lapses like these were 4.6 times more likely to have dementia than people without such episodes. In
addition, people with mental lapses tended to have more severe Alzheimer’s
symptoms and perform worse on memory and thinking tests.
"If you have these lapses, they don't by themselves mean that you have Alzheimer's," researcher James Galvin, MD, a Washington
University neurologist at Barnes-Jewish Hospital in St. Louis, says in a news
release. "Such lapses do occur in healthy older adults. But our results suggest
that they are something your doctor needs to consider if he or she is
evaluating you for problems with thinking and memory."
Previous studies have linked mental lapses with another type of dementia
known as dementia with Lewy bodies, but their association with Alzheimer’s
disease has been unknown.
Lewy body dementia causes clumps of proteins known as Lewy bodies to form in
neurons and is the most common form of dementia after Alzheimer’s disease. It
can overlap with Alzheimer’s disease as well as Parkinson’s disease.
New Alzheimer’s Symptoms?
In the study, published in Neurology, researchers evaluated 511 older
adults (average age 78) for Alzheimer’s disease and dementia. They also
interviewed participants and a family member for signs of mental lapses.
Researchers found that 12% of the participants met the criteria for
having mental lapses by having at least three of the following symptoms:
- Feeling drowsy or lethargic all the time or several times per day despite
getting enough sleep
the night before
- Sleeping two or more hours before 7 p.m.
- Having times when the person’s flow of ideas seems disorganized, unclear,
or not logical
- Staring into space for long periods
The study showed that people with three or four symptoms of mental lapses
were nearly 4.6 times more likely to be diagnosed with Alzheimer’s.
In addition, of the 216 diagnosed with very mild or mild dementia, 25 had
mental lapses compared with only two of the 295 without any signs of
"We have some ideas about why the biology of dementia with Lewy bodies
causes these mental lapses, but nothing comparable for Alzheimer's," Galvin
says. "It's possible that some of the patients who were diagnosed with
Alzheimer's disease in this study will go on to develop dementia with Lewy
bodies, but at the time of the study, they weren't showing any of the Lewy body
dementia's core features."
Researchers say more study is needed to determine whether to include mental
lapses in diagnostic tests for Alzheimer’s disease.