Cancer survival in California: Marriage helps, but benefit varies with demographics

It's widely known that your chances of surviving cancer are better if you're married.

But a new California-based study released today reports that the benefits of being married also vary by sex, race, ethnicity and birthplace, with white bachelors and white single women in the Golden State doing worse than their married counterparts.

The research also reveals that unmarried cancer patients born outside the U.S. have better survival rates compared to unmarried cancer patients born here.

"We're making the case that this is an important public health issue, and that there's a significant proportion of unmarried people with variation by race and ethnicity," said Maria Elena Martinez, a professor of Family Medicine and Public Health at UC San Diego, and the lead researcher of the report published today in the journal Cancer.

The premise behind the married/unmarried cancer survival rates gained a foothold in 2013, when a study published in the Journal of Clinical Oncology showed that married people with cancer were 20 percent less likely to die from their illness when compared with people who are separated, divorced, widowed or never married.

Experts believe the increased social support that goes along with being married helps someone's chances of overcoming the disease.

Spouses provide physical and emotional support to a partner with cancer, from driving their partners to medical appointments, to helping them navigate the health care system, to making sure their partners are eating and taking their medications.

All of that -- and more -- leads to higher psychological well-being, which many health experts believe improves outcomes for this group.

But Martinez's study -- which comes at a time when the numbers of unmarried adults in the U.S. is increasing -- digs deeper to determine which subgroups of unmarried people had better survival rates.

Armed with California Cancer Registry data from 2000 to 2009, Martinez and her team studied the outcomes of cancer patients in about 783,00 men and women.

Among other trends, the team noticed that unmarried men were more likely to live in poorer neighborhoods; had public, not private, insurance; were diagnosed with a late-stage cancer, and received less surgery and radiation than married males overall and within racial/ethnic groups.

The same conclusions held true with unmarried females, according to the Martinez report.

The research then showed that white male bachelors had a 24 percent higher cancer mortality rate compared to their married counterparts.

Single black and Hispanic men followed with a 20 percent higher mortality rate, while Asians and Pacific Islanders came in at an 11 percent higher death rate compared with married men in that ethnic group.

Unmarried white females, meanwhile, had a 17 percent increase in mortality compared with white married women, followed by single Hispanic women at a 11 percent higher death rate, black women at 9 percent, and unmarried Asian and Pacific Islander females who posted a 7 percent increase in cancer deaths compared with their wedded counterparts.

Martinez speculates that the single women's numbers are lower compared with single men because even single women have stronger social networks.

"Men don't have that -- they just don't form those bonds outside of marriage that women seem to form," Martinez said.

It's the same thing with racial groups, she said, noting that Hispanics and Asian Pacific Islanders "generally tend to have stronger bonds with our families and with our community culture.''

But the more assimilated to the U.S. culture they become, she said, leads to them lose those bonds and become more isolated. And that, she speculates, may be resulting in lower cancer survival rates in these unmarrieds.

A companion study, also appearing today in the journal Cancer, looked at the impact of socio-economic status on cancer survival.

The patterns in that study, led by Scarlett Lin Gomez, a research scientist at the Fremont-based Cancer Prevention Institute of California, also surprised the authors.

Gomez's research showed that worse survival rates in unmarried versus married cancer patients, especially among men, didn't have as much to to with differences in income, type of health insurance, or the type of neighborhood where they lived.

The study, Gomez said, seems to provide evidence that social support is a key driver in protecting unmarried cancer patients.

For now, both researchers said, it's imperative to disseminate this information to cancer patients and as well as those who are unmarried.

But physicians and health care providers also need to be on their toes.

"If a patient comes to your clinic and you see that they don't have someone with them,'' Martinez said, "a red flag should go up.''

Contact Tracy Seipel at 408-920-5343. Follow her at Twitter.com/taseipel.