Colon Cancer Screening Disparities Persist Among Medicare Patients

Abstract

Although Medicare coverage for colorectal cancer screening has increased, there are still significant disparities in screening practices on the basis of ethnicity, gender, age, education, and income level, according to a report in the Archives of Internal Medicine. Colorectal cancer is the third most common cancer affecting men and women in the United States, with approximately 145,290 new cases in 2005. There is evidence that screening for colorectal cancer decreases the incidence and mortality from this disease. Dr. Ashwin N. Ananthakrishnan and colleagues, at the Medical College of Wisconsin, Milwaukee, examined the 2002 and 2003 Medicare physician billing claims files for New York, Florida, and Illinois to identify rates of colon cancer screening tests in populations at average risk for this disease. Data from the US Census and the Medicare database were used to verify the gender, race or ethnicity, age, and social characteristics of the population, such as educational achievement and per capita income level of each patient based on their ZIP codes of residence. The type of screening test completed by each patient (fecal occult blood test, flexible sigmoidoscopy, double-contrast barium enema, and colonoscopy) was also noted. A total of 596,470 Medicare recipients were included in the study population with an approximately even number of patients in each age category (ages 65–69, 70–74, 75–79, and ≥80) and more women than men in all 3 states. The population was 89.5% Caucasian, 7% African American, and 2.1% Hispanic. An estimated 18.3% of the sample population was screened for colon cancer during the study period. “A larger percentage of the population had undergone a screening colon test in Florida (21.5%) compared with Illinois (16.6%) and New York (16.2%),” the authors write. “Blacks (9.7%) and Hispanics (8.1%) had lower rates of colon cancer screening compared with whites (19.3%),” they note. Individuals living in ZIP codes with a higher per capita income were more likely to undergo a colon cancer screening test than were those living in ZIP codes with a lower per capita income (21% and 14.6% in the highest and lowest tertiles, respectively). The study also found that women were less likely to undergo an invasive screening test or colonoscopy than men and that residing in a ZIP code with a more high school graduates was associated with an individual undergoing colon cancer screening. “Despite expanded Medicare coverage, there are still significant disparities in colorectal cancer screening practices,” the authors conclude. “Further research is needed to determine the basis for the observed ongoing disparities to develop interventions to reduce and eliminate these differences.” For more details, see “Disparities in colon cancer screening in the Medicare population,” Arch Intern Med 2007;167:258–264.