Scientists say they may have found the key to surviving cancer: marriage.
Married people with cancer were 20% less likely to die from their disease, compared to people who are separated, divorced, widowed or never married, according to study published online Monday in the Journal of Clinical Oncology.
Married people in the study fared better than singles no matter what type of cancer. In certain types of tumors — prostate, breast, colorectal, esophageal and head/neck cancers — the survival benefits of marriage were larger than those from chemotherapy.
"Improving social support for our patients may be equally important as providing effective therapy, and it is less costly to develop and implement," said senior author Paul Nguyen, a radiation oncologist at Dana-Farber Cancer Institute and Brigham and Women's Hospital in Boston, in a statement.
The real secret to survival may be "social support," rather than a wedding ring, said first author Ayal Aizer, chief resident of the Harvard Radiation Oncology Program in Boston, in a statement.
Spouses provide many practical services, nursing their partners through therapy, driving them to the hospital, helping with medications and making sure that patients eat well.
This kind of help can allow patients to complete recommended therapy, rather than skip treatments or drop out early, Aizer said.
Other studies have shown that married people are more likely than singles to stick with a treatment plan, even when that therapy is physically punishing or requires frequent trips to the hospital.
Belonging to a close family boosts the odds that a patient will stick with treatment by 70%, according to an accompanying editorial written by David Kissane, of Memorial Sloan-Kettering Cancer Center and Weill Cornell Medical College in New York.
Spouses also provide affection and moral support, which can be critical during cancer therapy.
Earlier research also has shown that married patients "display less distress, depression and anxiety than their unmarried counterparts," the study says. While stress can take a toll on the body, depression also can prevent patients from getting out the door to the doctor.
Other studies have found that depressed patients with cancer are up to 39% more likely to die than others, Kissane writes.
Of course, researchers couldn't actually test marriage vs. chemo in a head-to-head trial.
While marriage was associated with a better prognosis, a study like this — in which authors examined the records of 734,889 Americans diagnosed with cancer from 2004 to 2008 — can't definitively prove that being married allowed patients to survive. To truly prove cause and effect, researchers would have had to randomly assign people to be married or single.
It's possible, authors say, that married people were more likely to survive because they have lower rates of smoking and heavy drinking, a finding shown in previous studies.
But marriage also may allow people to take better care of themselves, the study suggests.
Among patients with cancer, married people were 17% more likely than singles to be diagnosed at an earlier stage, when cancer is more curable, according to an analysis of a National Cancer Institute database of 734,889 Americans. It's possible, doctors say, that spouses encourage their partners to see a doctor at the first sign of a problem, rather than wait until it gets worse.
Married folks were also 50% more likely to get the "definitive" treatment, or therapy most likely to result in a cure.
Men got more of a survival boost from marriage than women, the study says.
"We don't just see this as an affirmation of marriage," Nguyen said in a statement. "Rather, it should send a message to anyone who has a friend or loved one with cancer: By being there for that person and helping them navigate their appointments and make it through all their treatments, you can make a real difference to that person's outcome."
Researchers had to adjust their findings for differences between married and single patients. For example, married patients were more likely to be white and better educated. They were also more likely to be younger and male, perhaps because older women were more likely to be widowed. Still, researchers say the trend held up, even after considering these and other factors that could have skewed their results.
The study's findings suggest that doctors should consider screening unmarried cancer patients for depression. Unmarried cancer patients may be a high-risk group that hospitals should work extra hard to help, authors write.
"We have made substantial scientific progress in cancer treatment, but these gains need to be framed around the whole patient, their access to care and support systems," Gregory Masters, an oncologist and spokesman for the American Society of Clinical Oncology, said in a statement. "This study shows that spousal support is critically important in improving outcomes for patients with cancer. But for unmarried patients, the entire caregiver team — nurses, social workers, psychologists — needs to provide and help identify additional sources of social support."