Fundamental causes of colorectal cancer outcomes

"Those living in low socioeconomic status counties have yet to benefit from advances made in preventing colorectal cancer deaths more than 30 years ago, whereas those living in high socioeconomic status counties have seen a 33 percent to 50 percent reduction in mortality," said Andrew C. Wang, M.P.H., research assistant and student at Columbia University's Mailman School of Public Health, New York.

Colorectal cancer is a major cause of mortality; last year alone 16.2 people out of 10,000 died from this form of cancer, according to the researchers.

Experts believe that a few theories may help to explain why inequalities in colon cancer mortality rates exist. The first theory, fundamental cause theory, suggests inequalities exist because of the unequal access to resources. This theory works in part with access to health care. Diffusion of knowledge is the theory that the speed of new medical innovations may affect inequalities.

Wang and colleagues used administrative and U.S. census data from 2005 to pinpoint colon cancer mortality rates among whites and blacks from more than 3,000 counties.

Decreased mortality from colorectal cancer was associated with access to health care, living in states with histories of quicker uptake of new information and adoption of technology, and being in a higher socioeconomic county. Most importantly, Wang said, socioeconomic status acted as a form of a catalyst -- access to health care and diffusion of knowledge made only a limited difference in low socioeconomic counties, but clearly lowered colorectal cancer mortality rates for high socioeconomic status counties.

Health care professionals are now faced with the challenge to ramp-up efforts to reduce colorectal cancer mortality rates among individuals in low socioeconomic status areas, according to Wang.

"The medical and non-medical communities are not doing enough to prevent colorectal cancer," he said. "Much more can be done for those who are disadvantaged."

This research was recently presented at the American Association for Cancer Research 101st Annual Meeting 2010.