The results of a Finnish study published in Stroke (September 2003) indicate that 3 widespread viruses up the risk that elderly people will develop dementia. During the 1-year study, participants with a history of infection with at least 2 of the viruses?2 strains of herpes and a microbe called cytomegalovirus?were ~2 times as likely to show a dramatic mental decline, compared with participants infected with 1 or none of the pathogens.
According to the researchers, both herpes and cytomegalovirus are known to damage brain cells. Therefore, infection with either or both could lead to loss of neurons, and eventually dementia. Experts are increasingly recognizing that brain diseases have some connection with inflammation, and the National Institutes of Health is sponsoring a symposium on that topic later this year.