How Chronic Stress May Increase the Likelihood of Developing Alzheimer’s Disease

• Researchers say chronic stress may be one of the factors involved in the development of Alzheimer’s disease.
• They say constant stress can affect the brain’s immune system in a way that may lead to dementia symptoms.
• Experts say people can reduce stress by exercising, developing good sleep habits, and setting aside time for relaxation.

Chronic stress may contribute to the development of Alzheimer’s disease.

That’s what researchers in Australia have determined in a new study.

The researchers say a link between stress and Alzheimer’s disease could be due to a response in a part of the body called the hypothalamic-pituitary-adrenal (HPA) axis, a pathway in the brain responsible for stress responses.

“What we know is that chronic stress does affect many biological pathways within our body. There is an intimate interplay between exposure to chronic stress and pathways influencing the body’s reaction to such stress,” said David Groth, PhD, a senior author of the study and an associate professor at Curtin University in Perth, Australia.

“Genetic variations within these pathways can influence the way the brain’s immune system behaves, leading to a dysfunctional response. In the brain, this leads to chronic disruption of normal brain processes, increasing the risk of subsequent neurodegeneration and ultimately dementia,” Groth said in a statement.

Both dysregulation of the HPA and raised levels of cortisol, a stress hormone, are common in people with Alzheimer’s disease. Experts say these elevated levels of cortisol may play a role in neurodegeneration.

“We don’t know what the chicken or the egg is here in regard to cortisol. As with most things involving complex degenerative diseases in the human body, there is likely a feedback loop where high levels of cortisol and neurodegeneration are feeding off of each other,” Dr. Ryan Townley, an assistant professor of neurology at the University of Kansas Alzheimer’s Disease Center, told Healthline.

“The brain is undergoing excessive stress in Alzheimer’s disease. In the early phases, there is hyperexcitability in the setting of early pathology,” he explained. “We often see weight loss occurring prior to dementia and a lot of this is muscle mass. Some in the field suspect this disease is more systemic than we currently realize and an overall stress response in the body could be part of this.”