Information about High Stress Levels and Dementia Risk

Johns Hopkins researchers have linked high levels of the stress hormone cortisol with poor cognitive performance in older individuals. Researchers examined the stress-cognitive function connection as part of the ongoing Baltimore Memory Study.

For this study, they gave 20 standard cognitive tests to 967 participants (average age 61) while measuring cortisol levels in their saliva. The tests provided information on cognitive abilities such as information processing speed, language skills, and verbal memory and learning.

Saliva samples were collected before, during, and after the individuals underwent the cognitive tests and again at the end of the study. The researchers found that as cortisol levels rose, cognitive performance declined in a manner comparable to what is seen with aging.

For example, the cortisol-related decline in language skills was similar to what would be expected from someone who had aged nearly six years. A possible explanation for the cortisol connection is that chronic stress leads to malfunctions in the brain pathway that both regulates cortisol production and influences the health of brain cells. This could result in a greater degree of wear-and-tear on the brain. However, it could also be that the more tired one gets over time, the worse one performs on these tests.

Publication Review By: Peter V. Rabins, M.D., M.P.H.

Published: 08 Mar 2011

Last Modified: 06 Oct 2011