Researchers found that of 168 ovarian cancer patients, there were 95 deemed to have "high social attachment" - meaning they had relationships that made them feel emotionally secure and closely connected to at least one other person.

And after almost five years, 59 percent of those women were still alive, versus 38 percent of patients with lesser emotional bonds.

The researchers are not sure of the reasons for the link. It seemed to go beyond practical factors, like having someone who helps you out day-to-day. But the study cannot say whether a close emotional relationship, itself, affects women's survival odds.

And a researcher not involved in the work cautioned against making too much of the findings.

It is "strictly a correlational study," said James C. Coyne, director of the behavioral oncology program at the University of Pennsylvania School of Medicine in Philadelphia, in an email.

"And," he told Reuters Health, it bears repeating that "correlations do not establish causality."

There could be various reasons for the connection between emotional support and survival, according Dr. Susan K. Lutgendorf of the University of Iowa in Iowa City, who led the new study.

"We're talking about people who feel a close connection with someone else. They feel they have someone they can confide in," Lutgendorf said.

One possibility is that women with such supportive relationships feel less stress - which, in turn, might affect their well-being in a number of ways. Based on other research, people who feel support from family and friends may stick with their medical treatment more closely, Lutgendorf noted.

But in past studies, she and her colleagues have seen some potential direct links. They've found that ovarian cancer patients' levels of "social attachment" seem to correlate with certain markers of inflammation and immune function, for instance.

Still, no one knows if close emotional relationships can actually boost women's cancer survival odds.

In fact, Coyne said, some clinical trials have looked at whether boosting social support, through support groups or psychotherapy, can extend cancer patients' lives.

"And the findings are universally negative," he said.

These latest results, reported in the Journal of Clinical Oncology, are based on 168 women who were followed from the time of surgery for their ovarian cancer. They all completed questionnaires on social support and depression symptoms.

Ninety-five women scored high enough to fall into the category of strong emotional support.

The researchers found that even when they weighed depression and other factors - like age and the stage of the cancer - emotional support, itself, was still linked to somewhat better survival.

Women who felt strong support were 13 percent less likely to die during the study period.

On the other hand, "instrumental" support was not tied to survival.

"That means having someone who can provide concrete support," Lutgendorf explained. "Do you have someone who can take you to and from doctor visits? Do you have someone who can get your groceries?"

She said it was surprising that type of support was not also linked to survival.

What does it all mean for women with ovarian cancer?

"Many women have wonderful support from family and friends," Lutgendorf said. "But if you think you need more support, you can reach out."

Cancer centers often have "wellness" services that offer support groups or other types of psychological and emotional help, Lutgendorf noted. There are also national resources, like the American Cancer Society.

Lutgendorf said doctors can also ask cancer patients about their relationships - whether they have "someone they can talk to," for instance. Doctors often do screening for depression, she noted, so they could ask about emotional support as well.

Support groups can indeed be helpful to patients who are interested, according to Coyne. But don't expect them to prolong your life, he said.

Coyne said that if he were to study the issue, he'd want to follow a larger group of women over time. He would want to monitor any "medically significant events" and see how social relationships helped women deal with those health problems.

"My basic hypothesis would be that women who have close relationships have more opportunities to be vigilant for and address surgical complications, (other concurrent illnesses) and signs of (cancer) recurrence in a timely fashion," Coyne said.

He was critical of the theory that emotional bonds could have effects on the immune system that boost cancer survival. For one, Coyne said, it's not clear yet whether and how various "immunological variables" affect cancer progression.

He cautioned against raising people's hopes on that front.

"Cancer patients are particularly vulnerable to unrealistic expectations that they can extend their life by strengthening their immune systems," Coyne said.

SOURCE: bit.ly/NH6ld5 Journal of Clinical Oncology, online July 16, 2012.

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