Racial Disparities in the Use of and Indications for Colorectal Procedures in Medicare Beneficiaries

Background: African Americans are diagnosed more frequently with colorectal carcinoma at a later stage compared with Caucasians. One potential reason for the disparity is a lower rate of screening examinations.

Methods: Using Outpatient and Physician-Supplier claims for all Medicare beneficiaries age > or = 65 years in 1999, indications for fecal occult blood testing (FOBT), sigmoidoscopy, colonoscopy, and barium enema were divided into diagnostic, surveillance, or screening categories. Annualized rates were calculated based on the number of eligible fee-for-service months.

Results: Rates of FOBT (18.24% vs. 11.86%; P < 0.001) and sigmoidoscopy (3.07% vs. 2.17%; P < 0.001) were higher in Caucasians compared with African Americans, whereas rates of barium enema were higher in African Americans (2.26% vs. 1.88%; P < 0.001). Colonoscopy use was more frequent among men only in Caucasians compared with African-Americans (8.00% vs. 6.97%; P < 0.001). For FOBT, sigmoidoscopy, and colonoscopy, the racial differences in procedures performed for diagnostic purposes were of smaller magnitude than for screening; and, for colonoscopy, the use of diagnostic procedures actually was higher for African Americans.

Conclusions: Racial disparities exist not only in the use of colorectal procedures but also in the indications for such testing, with African Americans less likely to undergo screening tests. The differences are consistent with delay in diagnosis until symptoms or signs develop and may contribute to disparities in cancer mortality.