Background: Moderate racial differences have been documented for individuals screened for colorectal cancer (CRC). However, little is known about whether these disparities have changed over time. This study aimed to examine the trends in screening disparities by race from 1992 to 2002.

Methods: The study population consisted of two cohorts: 50,186 Medicare beneficiaries diagnosed with CRC between 1992 and 2002 and 62,917 Medicare beneficiaries without cancer during the same time period. Both cohorts of subjects were 67 to 89 years of age and resided in 16 Surveillance, Epidemiology and End Results (SEER) regions of the United States. Screening procedures conducted between 6 months and 3 years prior to the date of diagnosis for CRC patients and prior to the index date for persons without cancer were identified from Medicare claims. Age‐gender‐adjusted percentages of persons receiving the fecal occult blood test (FOBT), sigmoidoscopy (SIG), or colonoscopy (COL) by year and race/ethnicity were reported. Multivariable logistic regression analysis was used to assess the relationship between race/ethnicity and the odds of receiving CRC screening over time.

Results: Overall screening rates were similar between patients with colorectal cancer and those without cancer for FOBT (19.8% vs. 23.1%), SIG (6.2% vs. 5.2%) and COL (1.8% vs. 1.7%). Furthermore, there were higher screening rates in 2002 than in 1992 for all screening modalities within both groups of subjects. In the cohort of patients with CRC, there were no significant racial disparities in receiving CRC screening prior to the date of diagnosis. For example, the odds ratio for receiving FOBT was 1.07 (95%CI: 0.98–1.17) for Blacks, 0.94 (95%CI: 0.82–1.08) for Asians and 0.83 (95%CI: 0.67–1.01) for Hispanics compared to Whites with CRC in 2000–2002. However, among those without cancer, there were racial/ethnic differences in the use of FOBT and SIG. From 1992 to 1995, Blacks and Hispanics were less likely than Whites to receive FOBT (OR=0.75, 95% CI: 0.65–0.87; OR=0.50, 95% CI: 0.34–0.72, respectively) but the racial gaps in screening slightly widened from 2000 to 2002 (OR=0.79, 95% CI: 0.72–0.85; OR=0.67, 95% CI: 0.54–0.75, respectively). In addition, Blacks and Hispanics were less likely than Whites to receive SIG from 1992 to 1995 (OR=0.75, 95% CI: 0.57–0.98; OR=0.29, 95% CI: 0.12–0.71, respectively), but the disparities also widened from 2000 to 2002 (OR=0.79, 95% CI: 0.68–0.93; OR=0.50, 95% CI: 0.35–0.72, respectively).

Conclusions: Among Medicare beneficiaries without cancer, screening rates for FOBT and SIG differed between Blacks and Whites, and Hispanics and Whites. These disparities decreased in the later years, but were not eliminated. For patients with colorectal cancer, there were no statistically significant differences in screening prior to the diagnosis between racial groups. Future studies should incorporate information on physician recommendations and language/cultural barriers in these and younger populations.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B32.