WASHINGTON, Jul 26 (Reuters) - A compound found in the brains of Alzheimer's
patients and those with mild brain problems could point doctors to people most
at risk of the deadly and incurable disease, researchers said on Tuesday.
The compound, myoinositol, had been known to exist before. But a team at the
Mayo Clinic in Rochester, Minnesota found levels were elevated in Alzheimer's
patients and in those with mild cognitive impairment.
They used magnetic resonance imaging (MRI) to measure myoinositol levels in
63 people with normal cognitive function, 21 with mild cognitive impairment and
21 with Alzheimer's.
Writing in the journal Neurology, the researchers--Dr. Kejal Kantarci and
Dr. Clifford Jack--said both patients with mild impairment and those with
Alzheimer's had higher-than-normal levels of the compound in their brains.
"There is no evidence that myoinositol causes Alzheimer's disease, but we
believe that the substance might be a marker of inflammatory changes in the
brain that are part of Alzheimer's disease," Jack said in a statement.
"Chemical abnormalities may precede the death of brain cells, and elevated
concentrations of this substance in people who have mild cognitive impairment
and Alzheimer's disease may correlate with the fact that there is a higher rate
of brain cell death occurring in these people than in elderly people who have
normal cognitive function."
Mild cognitive impairment is already known to precede Alzheimer's, although
not always. Tests can show which patients have milder problems and which have
Alzheimer's.
Jack said it is too soon to start measuring myoinositol levels in all older
patients with memory or cognition problems. "This should not be considered a
diagnostic test for early Alzheimer's disease at the present time," he said,
adding that more studies are being done.
More than 4 million Americans and 20 million people worldwide have
Alzheimer's.
