Married people who are diagnosed with the most common types of cancer are 20% less likely to die than patients who are single – and depending on the type of cancer they have, their odds of dying may be reduced by as much as 33%, new research shows.
That finding raises an intriguing question: Is it possible to identify the specific benefits of marriage and put them into a hypothetical "pill" that could give the same benefits to patients who are single?
It may sound far-fetched, but that's at least part of the motivation behind the new study, published online this week by the Journal of Clinical Oncology. The researchers noted that the National Cancer Institute and the rest of the National Institutes of Health spend about $5 billion each year to understand the molecular basis of cancer and to develop biological treatments. But medicine is only part of the story – social support can matter just as much when it comes to long-term survival, and only 51% of American adults are married, they wrote.
So the team, led by doctors from hospitals and research programs affiliated with Harvard Medical School, examined the medical records of 734,889 patients from across the country who were diagnosed with cancer between 2004 and 2008. Instead of focusing on a single type of cancer, as previous studies have, the team included patients with the 10 types of cancer that cause the most deaths: lung, colorectal, breast, pancreatic, prostate, liver, non-Hodgkin's lymphoma, head/neck, ovarian and esophageal cancer.
Marriage seems to benefit patients at all stages of illness, the researchers found. People with spouses were 17% less likely to be diagnosed with an advanced cancer that has already spread to another organ. For prostate cancer, the risk of being diagnosed with metastatic cancer was 48% lower for patients who were married; for breast cancer, the risk was 40% lower.
In addition, married patients whose cancer hadn't spread were 53% more likely than their single counterparts to opt for a "definitive" treatment, including surgery and radiation (the medical records did not include information about chemotherapy treatments). For some cancers, patients were as much as 76% more likely to get the definitive treatment. The researchers speculate that patients who were married were more likely to stick to their treatment than patients who didn't have that spousal support.
After controlling for demographic factors, as well as the severity of the cancer and the treatment plan followed, the researchers found that married patients were less likely to die of all 10 types of cancer analyzed. The benefits ranged from a 33% reduced chance of dying of head and neck cancer or non-Hodgkin's lymphoma to a 12% reduced chance of dying of liver cancer.
These benefits were not trivial. For patients with head and neck cancer, being married reduced the risk of death by 33% -- much more than the 13% reduced risk of death shown in previous studies to be offered by chemotherapy. Marriage was more helpful than chemotherapy for breast, prostate, colorectal and esophageal cancer as well.
Married people had better cancer outcomes than all categories of single patients – those who were never married, separated, divorced or widowed. Both husbands and wives reaped the rewards of marriage, but the benefits were greater for men than women.
This study couldn't answer the question of why marriage seemed to help cancer patients, but the researchers offered some theories. Spouses probably pushed patients to get to the doctor sooner (so that their tumors are caught at an earlier stage) and they probably encourage patients to get – and stick with – more aggressive treatment.
Though a cancer diagnosis would be upsetting to anyone, previous studies have found that married patients are less distressed, less anxious and less likely to be depressed than patients who are single. They also have lower levels of the stress hormone cortisol – and that puts their immune systems in a better position to fight tumors.
How can single people get the social benefits of marriage without being married? That's the key question that should be answered in future studies, the researchers wrote.
It should be possible to close that gap, Dr. David Kissane of Monash University wrote in an editorial that accompanies the study. He cited studies showing that people who are part of a "close and cohesive family" are 1.7 times more likely to stick with their cancer treatment and that people who get "practical support"are 3.6 times more likely to persevere.
Perhaps single patients should be screened for depression at the time of diagnosis, so they can be treated if necessary, Kissane wrote. Cancer patients who are depressed are 19% to 39% more likely to die of the disease, previous studies have found.
"Our humanity is relational in its essence – we are tribal people, drawn into connection with one another to share what is most meaningful and fulfilling in life," he wrote. "Our medicine needs to follow a parallel paradigm."
If it did, it could be as powerful as any pill.