Small, regular doses of aspirin taken for at least two years before the onset of dementia appear to reduce the risk of Alzheimer's disease, according to researchers reporting in the journal Neurology.

The researchers studied more than 5,000 residents of Cache County, Utah, all 65 or older, asking whether they were taking aspirin or nonsteroidal anti-inflammatory (NSAID) drugs and also inquiring about the incidence of Alzheimer's.

They reported that the incidence of Alzheimer's and other forms of dementia appeared to be 45 percent lower for those who took aspirin or an NSAID for more than two years.

"This evidence from Cache County suggests that the critical period is several years before the onset of dementia. The same finding emerged from a Rotterdam study that was published last fall," said Dr. John C.S. Breitner of the University of Washington.

Other sources: Neurology