IPR Research Notes

Daily Experiences Predict Changes in Stress Hormone

Spring 2007, Volume 29, Number 1

Emma Adam

A new study that takes a rare look at the physiological, social, and emotional dynamics of day-to-day experiences in real-life settings shows that when older adults go to bed lonely, sad, or overwhelmed, they have elevated levels of the stress hormone cortisol shortly after waking the next morning. This rise could help give them a needed boost of energy to meet the demands of their day, according to a recent study led by IPR Faculty Fellow Emma Adam.

When chronically elevated, cortisol is linked to depression and other health problems. But when experienced infrequently—after an occasional bad day, for example—elevated cortisol levels could help prepare the body to overcome stress and negative experiences. Even on a typical day, Adam and her colleagues found that cortisol levels are high upon waking, increasing in the first 30 minutes after awaking, then gradually decreasing to lower levels by bedtime.

But the day after older adults report experiencing negative emotions such as loneliness, the post-awakening boost in cortisol is even larger.

“Cortisol increases are a survival mechanism that help us to respond to stressful experiences and do something about them,” said Adam, who is assistant professor of human development and social policy.

Adam’s research team also found that on days where participants had lower levels of cortisol when they woke up, they experienced greater fatigue throughout that day. Thus, the study provides evidence that cortisol influences—and is influenced by—the daily experiences of older adults. The link between low cortisol and daily fatigue could also aid in future research to understand chronic fatigue.

As a member of Cells to Society (C2S): The Center on Social Disparities and Health housed within IPR, Adam is interested in linking social stress factors to biology and health, specifically to understand when overuse of biological systems designed to cope with stress can lead to disorder. The National Institute of Aging and the John Templeton Foundation supported this research.

The article, “Day-to-day dynamics of experience-cortisol associations in a population based sample of older adults,” by E. K. Adam, L. C. Hawkley, B. M. Kudielka, and J. T. Cacioppo appeared online in the Proceedings of the National Academy of Sciences in October.