THURSDAY, May 1, 2014 (HealthDay News) -- The marital vows to stay true "in sickness and in health" seem to apply more to wives than husbands when one of the spouses becomes seriously ill, according to novel new research.
Social scientists found that the risk of divorce among older married heterosexual couples rises when the wife, but not the husband, experiences a health crisis such as cancer, heart problems, lung disease or stroke.
"When the wives became ill, about 50 percent of the marriages ended in divorce," said study author Amelia Karraker, a postdoctoral researcher at the University of Michigan's Institute for Social Research. "We have strong prior [evidence] that there would be a gendered component to this, that it would be more likely that a wife's illness would be more strongly associated with divorce than a husband's. But it's encouraging to see it borne out in data."
The study is scheduled to be presented May 1 at the annual meeting of the Population Association of America in Boston. Research presented at scientific conferences typically has not been published or peer-reviewed and results are considered preliminary.
About 36 percent of all marriages end in divorce in the United States for any reason, according to the U.S. Centers for Disease Control and Prevention.
Karraker and her co-author analyzed 20 years of data on more than 2,700 heterosexual marriages. At the time of the first interviews in 1992, at least one of the spouses was over the age of 50.
The marital effect of the onset of four serious health crises -- cancer, heart problems, lung disease and stroke -- was examined, with more husbands than wives developing these conditions during the study.
Only a few prior studies have examined the role of poor health in subsequent divorce, with mixed findings, and most of these investigations examined younger couples, Karraker said.
She noted that the new study "speaks to a different season of life," but her data didn't indicate which spouse initiated divorce. Prior research suggests that women initiate about two-thirds of divorce proceedings.
If the wife decides to exit the marriage after she becomes ill, it may be because she's dissatisfied with how well her husband is caring for her, Karraker said. If the husband decides to leave, he may do so to pursue a relationship with a healthy partner.
The new study couldn't explain exactly why the divorce risk is elevated when wives become ill, but Karraker said she hopes to glean insight into these aspects through further research.
Markie Blumer, an associate professor of human development and family studies at the University of Wisconsin-Stout, said she hopes more studies such as this examine relationships as people move through middle and late adulthood.
Blumer, who praised the new study for its large sample size, said the results could spur important conversations and broaden support from clinicians and social services for couples experiencing the illness of one partner.
"I think it's really a wake-up call to people who are aging and their family members and health care providers that they need to be mindful about how an illness will affect your caregiving requirements," said Blumer, who wasn't involved in the new research. "Being a caregiver is one of the most stressful jobs a person can have."
The CDC offers more statistics on marriage and divorce.