A new study finds that when a married woman over the age of 50 develops a serious health condition, the marriage may end in divorce.

When a couple gets married they take a vow that they will stay together in sickness and in health. Now, a new study finds that when a wife becomes ill, the risk for divorce rises.

The study used 20 years of data from the Health and Retirement Study, an ongoing study of Americans over the age of 50, conducted by the Institute for Social Research at the University of Michigan.

The researchers analyzed 2,706 marriages to see how the marriages were affected when one partner developed heart problems, lung disease, stroke, or cancer. The study excluded skin cancer diagnoses.

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During the period studied, 31 percent of marriages ended in divorce. The onset of new chronic illness also increased over time, with husbands more likely than wives to develop serious health problems.

The study found divorce to be more likely following the onset of one of these serious illnesses if the wife, but not the husband, was sick. The strongest correlation was found in women who developed heart disease.

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Pointing out that the study didn’t analyze which partner initiated the divorce, study co-author Amelia Karraker, a researcher at the University of Michigan Institute for Social Research, told Healthline men may be uncomfortable in the caregiver role. “It’s more normative for women to provide care as opposed to men. We speculate that some men might not have been engaged in caring for children. Being in this caregiving role may make it more stressful for them,” said Karraker.

Karraker continued, “The role of marriage markets in older ages could be a factor. There are more women for every man, so an older unmarried man will have more potential choices than an older unmarried woman.”

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Emphasizing that more research is needed to understand these trends, Karraker said, “One step we could take is to actually test how caregiving plays out in these marriages when one spouse is sick. There are particular stressors that might help explain these numbers.”

Noting that providing support services for spousal caregivers could alleviate strain and prevent divorce later on, Karraker said it’s important to recognize that poor health can be a trigger for divorce. “Sick ex-wives may need additional care and services to prevent worsening health and increased health expenditures,” she explained.

With an aging population and the high costs associated with caregiving, Karraker suggested that policymakers should be aware of these trends so they can act upon them.

Finally, Karraker said, “Someone who is sick and gets a divorce may need to rely on a paid caregiver, which presents significant cost issues. Illnesses don’t just have consequences for those who get sick – they impact the lives of those around them as well.”

The study findings were expected to be presented May 1, 2014, at the annual meeting of the Population Association of America.

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