Men who have never been married are less likely to survive cancer than their married counterparts, and the mortality gap has widened over the last few decades, a new study suggests.
The study looked at changes in cancer survival in Norway over the past 40 years. In 1970, never-married men with cancer were 18 percent more likely to die than married men with cancer, and this risk increased to 35 percent by 2007, the researchers found. While never-married women were also less likely to survive cancer than married women, the difference between them remained relatively constant over the years.
The researchers said they don't know what's causing this growing disadvantage for unmarried men, but they hypothesized that it could be due to being in poorer health at the time of cancer diagnosis.
Experts in the U.S. said the cancer survival trend seen in Norway may be different from what's happening here, because of the countries' differing health care systems.
"[The effect] could be even worse in the U.S. because of the lack of access to health care," said Linda Waite, a sociologist at the University of Chicago, who was not involved in the study. "The health care system here is good, but only if you have access to it."
Marriage and mortality
Past research has shown that mortality rates from all causes are higher among unmarried people. People who have never been married — as opposed to those who are divorced or widowed — have the highest mortality rates.
Some studies show that this higher mortality rate for unmarried people has increased over time, though the reason behind this phenomenon is unclear. "This suggests an increasingly deteriorating health among never married [people] when compared to the married," said Håkon Kravdal, co-author of the new study.
In the new study, the researchers sought to find whether the association between marital status and cancer survival, specifically, had changed with time. Examining a database from 1970 through 2007 for the entire Norwegian population, researchers found 440,000 people diagnosed with cancer between the ages of 30 and 89, and they recorded their cause of death, marital status, education and other information.
The researchers found that men with cancer who had never been married had the greatest risk of death, regardless of various factors, such as age, education and cancer stage.
Moreover, they calculated that the mortality gap between never-married men and married men increased by 3.4 percent every 10 years.
Divorced and widowed men with cancer were also more likely to die than married men, though their risk didn't appear to increase with time.
The researchers saw a small rise in the cancer death risk for unmarried women compared with married women, but this result may have been due to chance.
"It’s always been bad for men," Waite said, adding that men often rely on their spouses to navigate health care systems.
Outlook getting worse
Marriage has a positive effect on health for both men and women because of the pressure a spouse exerts to eat right, exercise and visit the doctor when health issues arise, Kravdal said.
Kravdal said he thinks that the cancer survival outlook for unmarried people may be getting worse over time because "our society is becoming increasingly individualistic, with less caring for each other." Unmarried people now have less social pressure to keep up good health practices than in the past, he argued. The unmarried may be in poorer overall physical and mental health than the married by the time they are diagnosed with cancer, decreasing their chance of survival.
Waite said she thinks that the differences in cancer survival between those with partners and those without partners may be even bigger than the study found. The database the researchers used does not specify whether an unmarried person is living alone or cohabiting, and cohabiting people likely share the health benefits of married people, she said. This inclusion of cohabitating people likely drove up the overall survival rate of unmarried people.
But in any case, the study shows that "things are getting worse for the unmarried — at least in Norway — and we don't really know why," Waite said.
And with the changes happening in all societies, Kravdal adds, "I think the health advantages of having a partner will be greater in the future."
The study was published today (Oct. 13) in the journal BMC Public Health.
Pass it on: Now more than ever, men who have never been married may be less likely to survive cancer than married men.
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