Low socioeconomic status linked with more severe colorectal cancer

People living in economically deprived neighborhoods were more likely to be diagnosed with late-stage, non-localized colorectal cancer, even after researchers controlled for known colorectal cancer risk factors, according to data presented at the Third American Association for Cancer Research Conference on The Science of Cancer Health Disparities, being held Sept. 30-Oct. 3, 2010. "Community clinical practitioners should be encouraged to understand the neighborhood characteristics of their patients and use that information to guide their encounters with patients, to help reduce disparities for colorectal cancer, which is a preventable disease," said study author Chyke Doubeni, M.D., M.P.H., assistant professor of family medicine and community health at the University of Massachusetts Medical School.

Researchers evaluated data from the NIH-AARP Diet and Health Study, a prospective cohort of participants from six U.S. states and two metropolitan areas. Data were obtained from 1995 to 2003, and none of the participants had a history of colorectal cancer.

Socioeconomic status was based on an empirically derived neighborhood socioeconomic deprivation index from 2000 U.S. census data.

Findings revealed 6,934 cases of colorectal cancer among 560,288 eligible participants; 59 percent of these cases were non-localized, defined as regional, distant or unstaged tumors. After adjusting for age and sex, the researchers reported a colorectal cancer incidence of 17.5 per 10,000 person-years.

Those participants who resided in the least socioeconomically deprived neighborhoods had an incidence rate of 16.2 percent compared with 19.8 percent for those living in the most disadvantaged neighborhoods.

After further accounting for individual-level education, dietary patterns associated with the risk for colorectal cancer, history of smoking and body mass index, findings revealed that those in the most deprived neighborhoods had a 13 percent higher overall incidence of colorectal cancer and 15 percent higher incidence of non-localized colorectal cancer compared with those in the least deprived neighborhoods.

Doubeni and colleagues plan to evaluate potential differences between men and women and to evaluate underlying reasons for disparities, including failures along the continuum of care and health care utilization histories.

"We need to understand more about the health care utilization patterns of patients in poorer neighborhoods and obstacles to colorectal cancer screening in those neighborhoods," Doubeni said.

Source: American Association for Cancer Research