Research shows that stress may start taking a toll on the brain in early middle age. High levels of cortisol in subject’s blood were found to be associated with physical changes in the brain that are seen as precursors to AD and other forms of dementia.
More than 2,000 people were included in this study most of which were in their 40s, finding those with highest levels of cortisol performed worse on testing involving memory, organization, attention, and visual perception; links were strongest for women, remaining unclear whether women in midlife are under more stress or more likely to have stress manifested in higher cortisol levels.
Cortisol is necessary for life and is not completely bad, but stress can lead people to develop potentially problematic behaviors such as drinking, unhealthy foods, and smoking; cortisol is the tip of the iceberg when it comes to things happening in a person’s life and body, according to neuroscientist Bruce McEwen.
New research included volunteers from the 70 year old Framingham Heart Study, grandchildren from the original participants are now being studied, most of which are white, middle class and suburban: even these relatively young well off subjects showed signs of brain changes in scans and performance.The highest cortisol levels were found to be associated with brain changes that could be seen on MRI scans.
Cortisol doesn’t distinguish between mental and physical stress, meaning some of those with high levels may have had physical illness that drove levels up such as diabetes. Levels may also spike if they are already undergoing brain changes and be the result rather than cause, but is unlikely due to younger ages. It was noted that levels were on measured in the morning once and do not reflect changes over time or variations throughout the day.
Subjects were given tasks such as copying shapes shown or repeat stories told earlier. Differences in performance were subtle, researchers were not able to tell whether subjects had high/low levels based on how well the carried out tasks, it was more in terms of group averages the differences showed.
Studies have shown weaker than average performance on testing such as these are associated with higher risks of dementia later in life, meaning high stress levels in midlife may be a contributing factor to dementia. Researchers say gaining better understandings of this link may offer potential opportunities to reduce risks, as it has not been conclusively shown that lowering cortisol levels will reduce risk of AD.
Cortisol levels have been shown to be reduced with sleep, exercise, socializing, and mental activities including yoga and meditation; whether this translates into better preservation of the brain needs to be determined in clinical trials. It is never too late to adopt healthy lifestyle habits such as reducing stress, being active, exercising, consuming a healthy diet, and getting enough sleep to help the body and mind which does have the capacity for repairing.
