New research shows that sleep disturbances have a serious effect on the heart health of those who have suffered the loss of a spouse. Researchers from Northwestern and Rice Universities reveal that poor sleep affects the immune system resulting in chronic inflammation that makes those who are grieving more susceptible to heart disease and cancer.

The researchers also noted that grieving spouses have a higher risk of developing heart disease or dying within a year of their love ones’ death according to an article published in PsychCentral.

The study, known as Project Heart, compared widows and widowers suffering from sleep disturbances such as insomnia with those who were married or single and also affected by poor sleep patterns.

The found that the association between sleep disturbances and inflammation was two to three time higher in the grieving spouses, according to the authors.

“We think these individuals are more vulnerable to the negative effects of poor sleep,” said author Dr. Diana Chirinos, a research assistant professor of preventative medicine at Northwestern University Feinberg School of Medicine.

“They have been hit twice. The death of a spouse is an acutely stressful event, and they have to adapt to living without the support of the souse. Add sleep disturbances to this already stressful situation and you double the stressor. As a result, their immune system is more over activated.

Chirinos’ research coincides with previous published studies that show individuals who have lost a spouse within the past three months have higher levels of pro-inflammatory cytokines—immune markers that indicate inflammation in the bloodstream—and lower heart rate variability.

Both factors increase your risk of cardiac events, she says, including death. Heart rate variability is the variation in time between each heartbeat.

“We already knew bereaved people had higher inflammation and a higher risk of heart disease and dying within a year of the spouse’s death,” said Chirinos. “But what was causing it? Was it the grief or sadness itself, loneliness, or sleep?

“Now we know its not the grief itself,” she explained. “It is the sleep disturbances that arise from that grief.”

Her results showed the importance of getting treatment for sleep problems for the bereaved, she added.

“Sleep problems may be most detrimental to health after losing a spouse,” she said. “If someone is experiencing sleep problems shortly after the loss of a spouse, its important for them to seek treatment.”

Cognitive-behavior therapy is offered in all sleep clinics and is highly effective, says the expert.