A study finds the risk of marriage ending in divorce when a spouse falls ill is higher when that spouse is the wife.
The study was not designed to find out which spouse instigated the divorce - the healthy spouse or the sick spouse - so could not draw conclusions on causes. However, the researchers - from Iowa State University in Ames - did make some suggestions.
In the Journal of Health and Social Behavior, they describe how they analyzed the divorce rate in older couples where either the wife or the husband was diagnosed with one of four serious illnesses: cancer (except skin cancer), heart disease, lung disease and stroke.
The researchers were not surprised to find that when either spouse fell ill with one of these diseases, there was a raised risk that the most likely reason for marriages ending during the 20 years of the study was widowhood - that is, death of a spouse.
However, they also found that when the wife fell seriously ill over the course of the study, the risk of divorce was higher, but not when the husband was the sick spouse.
Illness can stress marriage in a number of ways
Lead author Amelia Karraker, an assistant professor of human development and family studies at Iowa State, says the data they analyzed could not explain the finding, but notes illness can stress marriage in a number of ways.
One way that spouse illness can stress a marriage is when the healthy spouse is the primary caregiver and may also have to take on sole responsibility for supporting the household. Prof. Karraker explains:
"There is a difference between feeling too sick to make dinner and needing someone to actually feed you. That's something that can really change the dynamics within a marriage. If your spouse is too sick to work, we know that financial strain is a major predictor of divorce in and of itself."
Another stressor can be differences about quality of care. Prof. Karraker says wives are generally less satisfied with the care they receive from their husbands, probably because - and this applies to older men in particular - men have not been raised to be caregivers in the same way as women and may feel uncomfortable when thrust into the role.
The data did not include information on which spouse initiated the divorces when they occurred, but the authors suggest that, in some cases, it could be women ending the marriage because of dissatisfaction with the care they receive.
Serious illness is a life or death experience that can make people stop and think about what is important in their lives, explains Prof. Karraker.
She says perhaps women are saying: "You're doing a bad job of caring for me. I'm not happy with this, or I wasn't happy with the relationship to begin with, and I'd rather be alone than be in a bad marriage."
Study found a significant gender difference in divorce following illness of a spouse
For their study, the authors analyzed data on married couples collected between 1992 and 2010 in the Health and Retirement Study.
They were interested in people who were married at the start of the study period, and because they wanted to examine the effect of falling ill during that period, they excluded marriages where a spouse was already sick at the beginning of the study.
In the end, their analysis included 2,701 marriages where one spouse was at least 51 years old at the start of the 20 years of data collection.
Over the period, 32% of the marriages ended in divorce compared with 24% that ended in widowhood - the death of either spouse. Divorce was more common among younger spouses, whereas widowhood was more common among older spouses.
When the researchers looked at illness, they found - unsurprisingly - that increasing age was tied to increased chance of getting a serious illness, with husbands experiencing higher rates than wives. They found the chances of widowhood went up by 5% when the husbands fell ill, and by 4% when the wives fell ill.
However, while the onset of illness in the husband was not linked with raised chance of divorce, illness in the wife was linked to a 6% higher risk of being divorced before the end of the study period. This was a significant gender difference.
Other studies have shown that being married is linked to better physical and mental health, but this study seems to show that illness may reduce these benefits for women.
Prof. Karraker says their findings demonstrate the ways that being sick can make people vulnerable in our society:
"There is an elevated risk for depression with illness and now you're also at risk for divorce. People in poor health may have less access to beneficial social relationships, which in turn can compromise their health further."
The researchers found some variation among the four illnesses they examined, but the result for each illness was not statistically significant.
The study was funded by the National Institute on Aging.
In 2011, Medical News Today learned that the phenomenon of women as caregivers for their ex-husbands is more common than we might expect. Some of the women who took part in the study also reported caregiving as a turning point in relationships with their ex-husbands.