Men, singles less likely to have colon cancer test

NEW YORK (Reuters Health) - Men, unmarried adults and those with low incomes are less likely to accept an offer of free colon cancer screening, a new study suggests.

Swedish researchers found that when they offered free sigmoidoscopy screening to nearly 2,000 adults ages 59 to 61, men were 27 percent more likely than women to decline. Meanwhile, those who were single or divorced were 69 percent and 49 percent, respectively, more likely to decline screening compared with married people.

A similar discrepancy emerged when the researchers looked at study participants by income. The one third of participants with the lowest incomes were 68 percent more likely to decline sigmoidoscopy screening than the one third with the highest incomes.

The researchers, led by Dr. Johannes Blom of the Karolinska Institute in Stockholm, report the findings in the International Journal of Cancer.

Sigmoidoscopy is one of the options for routine colon cancer screening, which experts recommend for most adults beginning at age 50; some higher-risk individuals may need to start screening earlier.

Sigmoidoscopy is similar to colonoscopy in that a thin, flexible scope is inserted into the colon to look for suspicious growths; in sigmoidoscopy, though, only the lower portion of the colon is inspected, whereas colonoscopy looks at the entire length of the colon.

Both exams can help detect colon cancer early, or prevent it by allowing the doctor to find and remove polyps -- growths that could become cancerous. Yet studies in different countries consistently show that colon cancer screening rates are lower than they should be.

Understanding which people are least likely to seek screening should help in targeting education, according to Blom’s team.

The study did not look at why men, singles and low-income adults were less likely to accept a free sigmoidoscopy. The researchers speculate on some potential reasons, however.

Although the test itself was free, they note, lower-income adults may have faced other obstacles -- like trouble taking the day off of work.

But it’s also likely, Blom told Reuters Health, that lower-income people are less aware of the rates of illness and death associated with colorectal cancer and the possible benefits of colorectal cancer screening.”

As for men’s greater resistance to screening, other research has shown that men tend to have less health knowledge than women, and are less likely to take preventive measures like screening tests.

Similarly, studies suggest that married people are more proactive about their health than single adults are, possibly because they have a spouse to nudge them.

In this study, the researchers used letters to invite people to have free sigmoidoscopy screening. But Blom said this might not be enough to reach people who are resistant to colon screening; it’s possible, he noted, that education campaigns over television, radio or the Internet might be more effective.

“This is speculative, but an opportunity for future research,” he said.

SOURCE: International Journal of Cancer, April 1, 2008.