Common Infections May Increase Risk of Memory Decline
Researchers link antibody levels to worsening cognitive function (February 13)
Exposure to common infections is linked to memory and brain function, even if the infections never made people ill, according to new research presented at the American Stroke Association’s International Stroke Conference 2014, held in San Diego, California.
Researchers found that antibody levels caused by exposure to Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpes simplex viruses 1 and 2 were associated with worse cognitive performance, including memory, speed of mental processing, abstract thinking, planning, and reasoning ability.
Earlier studies have already linked certain infections to an increased risk of stroke and Alzheimer’s disease. Researchers investigated whether evidence of past exposure to these infections affected performance on tests of memory, thinking speed, and other brain functions.
In the new study, the researchers conducted brain-function tests and took blood samples from 588 people who participated in the Northern Manhattan Study. Half of the participants took cognitive tests again in 5 years.
Experts already believe that exposure to these infections may be associated with an increase in stroke risk, as well as with an increase in atherosclerosis and inflammation, according to lead researcher Clinton Wright, MD, MS.
The new study doesn’t explain why the infections are related to worsening cognitive function. “It could be caused by an immune system response to the infections, or the infection itself could result in clinical damage that we’re not aware of,” Wright said.
Source: American Heart Association; February 13, 2014.