Providing a new possible link between the mind and body, a study says women under chronic stress have significantly lower levels of klotho, a hormone that regulates aging and enhances cognition.
The women with clinically significant depressive symptoms had even lower levels of klotho in their blood than those who were under stress but not experiencing such symptoms.
The study, published in Translational Psychiatry, is the first to show a link between psychological influences and klotho.
"Our results suggest that klotho, which we now know is very important to health, could be a link between chronic stress and premature disease and death," said lead author Aric Prather, an assistant professor of psychiatry at University of California, San Francisco (UCSF).
Based on research in mice and worms, scientists know that when klotho is disrupted, it promotes symptoms of aging and when klotho is made more abundant, the animals live longer.
The study included 90 high-stress caregivers and 88 low-stress controls, most of whom were in their 30s and 40s and otherwise healthy.
Klotho is known to decline with age, but in this cross-sectional study of relatively young women, this decline only happened among the high-stress women.
The low-stress women did not show a significant reduction in klotho with aging.
"Chronic stress transmits risk for bad health outcomes in aging, including cardiovascular and Alzheimer's disease," said Dena Dubal, an assistant professor in the UCSF department of neurology.
"It will be important to figure out if higher levels of klotho can benefit mind and body health as we age. If so, therapeutics or lifestyle interventions that increase the longevity hormone could have a big impact on people's lives."