The family of Debbie Reynolds would not be surprised to learn that a mother's heartbreak can be fatal.
A stroke reportedly took the life of the 84-year-old Hollywood actress just a day after the death of her daughter, Carrie Fisher, who played Princess Leia in the Star Wars films. Ms. Reynolds is said to have told relatives that Ms. Fisher's death was "just too much."
Research is beginning to suggest that for some parents, and especially mothers, the loss of a child really can be too much. A wide-ranging 2012 study found that mothers in the U.S. had a 133-per-cent higher risk of dying in the two years after their child's death. The pattern held regardless of the mother's marital status or education, or the child's cause of death or gender.
A team of researchers at Houston's Rice University, meanwhile, is trying to learn more about why grief takes such a punishing physical toll. The consecutive deaths of Ms. Fisher and Ms. Reynolds "really [do] fit in perfectly, in a very sad way, with what we're doing in the lab right now," said assistant psychology professor Chris Fagundes on Thursday.
In his studies of bereaved people, Dr. Fagundes is looking at how the stress of grief can contribute to heart disease and stroke. The sustained stress caused by the loss of a loved one – often a spouse, in the Rice University research – can promote chronic inflammation in a person's blood cells, as though they were fighting off a long-lasting infection.
That inflammation causes swelling in the arteries that can break off quantities of plaque and block part of the circulatory system leading to the heart or brain.
"When you're in a depressive state, any spike in stress causes a huge spike in inflammation," said Dr. Fagundes.
Previous studies have looked at the "widowhood effect," in which widows and widowers become likelier to die shortly after the death of their spouse. A 2013 study led by researchers at the Harvard School of Public Health found the effect was strongest in the three months following a partner's death, when the surviving spouse's chance of dying increased by 66 per cent.
Studies have also turned up an empirical connection between bereavement and worsened health in grandparents, children and siblings.
Research on the mortality risk for parents who have lost a child has been scant by comparison, perhaps because in Western countries the experience is relatively uncommon. But there are reasons to think that mothers especially could be prone to health downturns related to grief.
Women are roughly twice as likely as men to develop major depression and, as Dr. Fagundes notes, depressive symptoms are linked to stress-induced inflammation that can lead to heart attacks. Older women face the added challenges of a post-menopausal drop in estrogen, a hormone that has been found to have anti-inflammatory properties in some cases.
Elderly women are also most likely by far to suffer from "broken-heart syndrome," or takotsubo cardiomyopathy as it's known to scientists. The little-understood condition consists of a weakening of the left ventricle, part of the heart's pumping mechanism, usually as the result of intense stress, including the loss of a loved one (hence its colloquial name). Women between the ages of 58 and 75 represent more than 90 per cent of reported cases.
Still, the health of young and middle-aged mothers can take a major hit with the death of a child, too. The 2012 study on maternal bereavement and mortality, led by Javier Espinosa and William Evans, looked at more than 69,000 mothers between the ages of 20 and 50.
And a British study published in 2011 showed that mothers who lost a child in the first year of its life were more than four times more likely to die within 15 years as mothers who had not suffered a comparable loss.
The causes of maternal death by heartbreak remain unclear. Dr. Espinosa and Dr. Evans note that research linking maternal bereavement and increased risk of cancer may be related to self-destructive lifestyle changes brought on by stress.
If inflammation is the answer, or part of it, as the work being done at Rice University suggests, there are ways to curb the problem: Dr. Fagundes recommends yoga for its stress-reducing effects, aspirin for its anti-inflammatory qualities, and a diet rich in omega-3 fatty acids for the same reason (salmon is a good source of the latter).
None of this would have helped Ms. Reynolds, who died so soon after her daughter, before any regimen could intervene. But then, there is some evidence that the beloved star of movies like Singin' in the Rain didn't want to be helped.
In an interview with the Associated Press, Ms. Fisher's brother, Todd, described their mother's final moments.
"She said, 'I want to be with Carrie,'" he recalled. "And then she was gone."