Marriage improves odds of surviving colon cancer

Similar to studies of other types of cancers, the researchers did find that married people were diagnosed at earlier stages of colon cancer and sought more aggressive treatment. The researchers took those and other factors into account before calculating the benefit of marriage on survival odds.

"Controlling for the stage that the cancer was detected is key," said Sven Wilson, a study coauthor and professor at Brigham Young University. "Without that, it's hard to know whether the analysis is just picking up a diagnosis effect."

Colon cancer is the fourth most common type of cancer in the United States for both men and women. Curiously, the marriage benefit seen in the new study was nearly identical for both men and women.

So what's driving the different survival rates? Marriage is a self-selected group, and Wilson is careful to note that the selection process makes it difficult to sort out the root cause. One intuitive idea is that spouses serve as an important informal caregiver during a critical time, and that extra support may translate into better disease management and, hence, better outcomes.

The journal Cancer Epidemiology published the new study online in advance of its print publication. Penn State's Li Wang is the lead author. BYU graduate Chris Hollenbeak, who is now a faculty member at Penn State's College of Medicine, is also a coauthor on the study.