Race disparities in colonoscopy screening among persons with a family history of colorectal cancer

Background: A family history of colorectal cancer (CRC) is a risk factor for CRC; 20% of newly diagnosed CRC patients report a family history compared to only 11% of the general population. According to guideline recommendations persons with a positive family history should undergo colonoscopy screening every five years from 40 years of age. Because African Americans (AA) suffer 46% higher CRC mortality than Whites despite only 16% higher incidence, one question arises whether AAs with a CRC family history, particularly younger AAs are receiving colonoscopy screening at similar rates as Whites. Among AAs, 10.6% of CRCs are diagnosed before 50 years of age compared to only 5.5% among Whites.  The Southern Community Cohort Study of community health center outpatients during 2002-2006 reported that 27.3% and 43.1% of AAs and Whites, respectively had received a screening colonoscopy. This study examines the screening patterns among the US general population with a family history of CRC.    

Methods: To investigate racial differences in colonoscopy screening among Americans with a CRC family history using data from the National Health Interview Survey 2010.

Results: Of 6,344 respondents to questions on CRC family history, 1,124 (17.7%) reported a CRC family history (mean age 62.3 (SD: 12.6)). Of 1,124 respondents 46.2% had a colonoscopy in the previous 5 years (49.3% among Whites and 34.5% among AAs). Among the 40-49 age group, AAs had 45.7% lower colonoscopy rates than Whites (20% vs. 36.8%). Disparity persists in older age groups but reduced to 24.9% in the 65-plus age group. Multivariate analysis showed that after accounting for socio-demographic factors and insurance status, AAs and Whites with high school or less education were 68% and 33% less likely than Whites with a bachelor’s degree or higher to have been screened. There were no racial differences in screening likelihood among categories with any college education. Respondents aged 40-49 years were 40% less likely to be screened than the 50-64 age group. Insurance type was a major predictor; those with Medicare (alone or in combination) had the highest likelihood of being screened (OR range, 5.0 to 5.6) relative to the uninsured.

Conclusion: Significant racial disparity in screening exists, particularly in the 40-49 age group. Education and insurance are the key mediating factors. Studies after 2015 will indicate whether the Affordable Care Act narrows the disparity. Targeted patient navigation may increase screening rates among less educated and younger Americans with CRC family history.