Grief linked to sleep disturbances that can be bad for the heart

The study, "Bereavement, self-reported sleep disturbances and inflammation: Results from Project HEART," was recently published in Psychosomatic Medicine. It compared the self-reported sleep habits of recently widowed people to a control group. Both groups had sleep disturbances, such as insomnia.

The researchers found that the link between sleep disturbances and inflammation was two to three times higher for the bereaved spouses. Inflammation was measured by the level of proinflammatory cytokines, which are designed to be short-term fighters of disease but are linked to long-term risk for health problems including cardiovascular disease.

Corresponding author Diana Chirinos, a research assistant professor of preventive medicine at the Northwestern University Feinberg School of Medicine who began examining the topic as a Rice Academy postdoctoral fellow in Rice's Department of Psychological Sciences, said the study suggests that these bereaved individuals are more susceptible to the negative health effects of poor sleep.

"The death of a spouse is an acutely stressful event and they have to adapt to living without the support of the spouse," she said. "Add sleep disturbance to their already stressful situation and you double the stressor. As a result, their immune system is more overactivated."

Chirinos said she and her fellow researchers already knew widowed individuals had higher levels of inflammation. Prior work revealed that in the first six months after the loss of a spouse, widows and widowers are at a 41 percent higher risk of mortality, and 53 percent of this increased risk is due to cardiovascular disease. However, they wanted to find the specific cause.

"Now we know it's not the grief itself; it is the sleep disturbance that arises from that grief," Chirinos said.

Chris Fagundes, an assistant professor of psychological sciences at Rice and the principal investigator for Project HEART, said the finding is another revelation in the study of how human behaviors and activities impact inflammation, and it adds to a growing body of work about how bereavement can affect health. His initial work showed why people who have been widowed are at higher risk of cardiovascular problems and premature death by comparing their inflammation with matched controls.

"While working in my laboratory as a post-doctoral fellow, Diana did a great job incorporating her expertise in sleep data collection into this project," he said.

Ultimately, the researchers hope the findings will help to design better health interventions for those suffering from loss.

The study included 101 people with an average age of 67. Half were bereaved (identified through obituaries), and the rest made up the control group.