In a study of 50 women, about half of them caring for relatives with dementia, the psychologists found that those most threatened by the anticipation of stressful tasks in the laboratory and through public speaking and solving math problems, looked older at the cellular level. The researchers assessed cellular age by measuring telomeres, which are the protective caps on the ends of chromosomes. Short telomeres index older cellular age and are associated with increased risk for a host of chronic diseases of aging, including cancer, heart disease and stroke.
"We are getting closer to understanding how chronic stress translates into the present moment," said Elissa Epel, PhD, an associate professor in the UCSF Department of Psychiatry and a lead investigator on the study. "As stress researchers, we try to examine the psychological process of how people respond to a stressful event and how that impacts their neurobiology and cellular health. And we're making some strides in that."
The researchers also found evidence that caregivers anticipated more threat than non-caregivers when told that they would be asked to perform the same public speaking and math tasks. This tendency to anticipate more threat put them at increased risk for short telomeres. Based on that, the researchers propose that higher levels of anticipated threat in daily life may promote cellular aging in chronically stressed individuals.