Stress and Alzheimer's possibly linked

SAN DIEGO (UPI) -- The stress of everyday life may add to the accumulation of neurofibrillary tangles, one of the hallmarks of Alzheimer's disease, suggests a U.S. study.

Researchers at the Salk Institute for Biological Studies in San Diego say that aging is still the greatest risk factor for Alzheimer's disease, a number of studies have pointed to stress as a contributing factor.

"A long-term study of about 800 members of religious orders had found that the people who were most prone to stress were twice as likely to develop Alzheimer's disease, but the nature of the link between the two has been elusive," study leader Paul E. Sawchenko, said in a statement.

The findings, published in the Journal of Neuroscience, suggest that the brain-damaging effects of negative emotions are relayed through the two known corticotropin-releasing factor receptors, CRFR1 and CRFR2, which are part of a central switchboard that mediates the body's responses to stress and stress-related disorders.