Stress and Diabetes: What's the Link?
Researchers have found a link between emotional stress and diabetes, with roots in the brain’s ability to control anxiety.
That control lies with the brain’s executive functions, processes that handle attention, inhibition, working memory and cognitive flexibility and are also involved in reasoning, problem-solving and planning.
The study by Rice University researchers, published in Psychoneuroendocrinology, establishes a metabolic chain reaction that starts with low inhibition, a/k/a attention control, which leaves a person vulnerable to tempting or distracting information, objects, thoughts or activities. Previous studies have shown that such vulnerability can lead to more frequent anxiety, and anxiety is known to activate a metabolic pathway responsible for the production of pro-inflammatory cytokines, signaling proteins that include interleukin-6 (IL-6).
Along with cognitive tests that measured attention control, the Rice study measured levels of both blood glucose and IL-6 in more than 800 adults. IL-6 is a protein the body produces to stimulate immune response and healing. It is a biomarker of acute and chronic stress that also has been associated with a greater likelihood of diabetes and high blood glucose.
The research showed individuals with low inhibition were more likely to have diabetes than those with high inhibition due to the pathway from high anxiety to IL-6. The results were the same no matter how subjects performed on other cognitive tests, like those for memory and problem-solving.
Researchers have suspected a link between anxiety and poor health, including diabetes, for many years but none have detailed the biological pathway responsible, said lead author Kyle Murdock, a postdoctoral research fellow in psychology. He said the Rice study takes a deeper look at how inflammation bridges the two.
“The literature shows individuals with poor inhibition are more likely to experience stressful thoughts and have a harder time breaking their attention away from them,” Murdock said. “That made me wonder if there’s a stress-induced pathway that could link inhibition with inflammation and the diseases we’re interested in, such as diabetes.
“Plenty of research shows that when individuals are stressed or anxious or depressed, inflammation goes up,” he said. “The novel part of our study was establishing the pathway from inhibition to anxiety to inflammation to diabetes.”
Murdock works in the Rice lab of Christopher Fagundes, assistant professor of psychology. The Fagundes lab investigates processes that happen along the border of psychology and physiology, and how those processes affect overall health and potential treatments.