Background: Lower rates of screening among minorities and low-income populations contribute to colorectal cancer health disparities. Therefore, we examined patterns of colorectal cancer screening and associations with race-ethnicity, education, and income over time.
Methods: Repeated cross-sectional data from the Medicare Current Beneficiary Survey of noninstitutionalized colorectal cancer-free Medicare enrollees ages 65 to 80 years interviewed in 2000 (n = 8,355), 2003 (n = 7,922), and 2005 (n = 7,646). We examined rates of colonoscopy/sigmoidoscopy use within 5 years (recent endoscopy), colonoscopy/sigmoidoscopy use >5 years previously, or fecal occult blood test (FOBT) within 2 years.
Results: Among those included in the analyses, there was a steady increase in recent endoscopy rates and decrease in FOBT use over the 6-year period among all racial, educational, and income groups. During each of the survey years, those less educated or in lower-income groups were less likely to undergo colorectal cancer screening in a dose-response fashion. In multinomial regression analyses that adjusted for factors including health insurance, there were no significant differences in recent endoscopy or FOBT rates between Blacks or Hispanics and Whites, but differences by education and income remained. Compared with those in higher-income group, lower-income enrollees had lower rates of screening, and differences by income were larger for enrollees residing in metropolitan areas.
Conclusion: Among Medicare beneficiaries, there are persistent colorectal cancer screening disparities due to a complex combination of socioeconomic disadvantages from lower education and income, place of residence, and inadequate insurance. However, insurance alone does not eliminate socioeconomic differences in colorectal cancer screening.