Alzheimer's, Dementia & Mental Health
Cold or Stomach Bug May Provide Infection to Hasten
Memory Loss in Alzheimers Patients
More likely to experience memory loss or
cognitive decline than people who did not have infections
Sept. 7, 2009 - Getting a cold, stomach bug or
other infection may lead to increased memory loss in people with
Alzheimer's disease, according to research published in the September 8,
2009, print issue of Neurology, the medical journal of the
American Academy of Neurology.
The study found that people who had respiratory,
gastrointestinal or other infections or even bumps and bruises from a
fall were more likely to have high blood levels of tumor necrosis
factor-α, a protein involved in the inflammatory process.
They were also more likely to experience memory
loss or other types of cognitive decline than people who did not have
infections and who had low levels of the protein.
The blood levels and cognitive abilities of 222
people with Alzheimer's disease with an average age of 83 were measured
at the beginning of the study and three more times over six months.
Caregivers were interviewed to determine whether the participants had
experienced any infections or accidental injury that could lead to
inflammation.
A total of 110 people experienced an infection or
injury that led to inflammation during the study. Those people
experienced memory loss that was at twice the rate of those who did not
have infections or injuries.
People who had high levels of the protein in their
blood at the beginning of the study, which may indicate chronic
inflammation, had memory loss at four times the rate of those with low
levels of the protein at the start of the study.
Those who had high levels of the protein at the
start of the study who also experienced acute infections during the
study had memory loss at 10 times the rate of those who started with low
levels and had no infections over the six-month period.
"One might guess that people with a more rapid rate
of cognitive decline are more susceptible to infections or injury, but
we found no evidence to suggest that people with more severe dementia
were more likely to have infections or injuries at the beginning of the
study," said study author Clive Holmes, MRCPsych, PhD, of the University
of Southampton in the United Kingdom.
"More research needs to be done to understand the
role of tumor necrosis factor-alpha in the brain, but it's possible that
finding a way to reduce those levels could be beneficial for people with
Alzheimer's disease."
The study was supported by the Alzheimer's Society
in London, UK.
The American Academy of Neurology, an association
of more than 21,000 neurologists and neuroscience professionals
dedicated to promoting the highest quality patient-centered neurologic
care through education and research.
For more information about the American Academy of
Neurology, visit
www.aan.com or
www.thebrainmatters.org.