Racial and Ethnic Disparities in Colorectal Cancer Screening Pose Persistent Challenges to Health Equity

Colorectal cancer (CRC) screening is a widely endorsed, cost-effective means of reducing CRC incidence and mortality, but screening rates have been suboptimal: in 2008, just 53.1% of age-eligible individuals were reported as being up-to-date with CRC screeing.^1–3 Disparities in screening uptake across racial/ethnic minorities exist, with lower rates among blacks, Hispanics, Asians, Native Hawaiian/Pacific Islanders, and American Indians/Alaska Natives compared with non-Hispanic whites. Prior initiatives to increase screening have included the decennial Health People Initiative to reach 70.5% screening by 2020, efforts of the National Colorectal Cancer Roundtable and the Centers for Disease Control and Prevention to promote evidence-based interventions to promote screening, inclusion of CRC screening as a quality metric for private insurers and Medicare, and passage of the Patient Protection and Affordable Care Act (ACA) in 2010. The elimination of cost-sharing for specific preventive screening tests in ACA and such targets as the National Colorectal Cancer Roundtable goal of 80% CRC screening uptake (now a 2020 goal of 80% screened in every community) set the stage for potential substantial improvements in CRC screening uptake. However, it is unclear how these policies and goals might have impacted racial/ethnic screening disparities. Findings from the study in Clinical and Gastroenterological Hepatology by May et al⁴ provide key evidence indicating that, whereas CRC screening rates might be improving nationally, racial/ethnic disparities in uptake are persisting, and in some cases getting worse.

Using data from the nationally representative Behavioral Risk Factor Surveillance System, May et al⁴ measured trends in self-reported CRC screening status from 2008 to 2016 to examine whether screening rates improved in the United States, and whether there were any changes in racial/ethnic screening disparities. For all racial/ethnic groups combined, CRC screening uptake increased from 61.1% in 2008 to 67.6% in 2016. However, variation in improvement was observed across racial ethnic groups, with uptake from 2008 to 2016 increasing from 63.9% to 70.4% for whites, 60.6% to 66.4% for blacks, 44.7% to 53.4% for Hispanics, 51.1% to 63.2% for Asians, 60.2% to 69% for Native Hawaiian or Pacific Islanders, 55.2% to 59.4% for American Indians or Alaska Natives, and 54.6% to 65.5% for individuals identifying as multiracial or other. Although disparities in the proportion screened (expressed as an absolute difference) between non-Hispanic whites and most groups narrowed over time, these reductions were small for most comparisons: 2.2% for Hispanics, 5.6% for Asians, 2.3% for Native Hawaiians or other Pacific Islanders, and 4.7% for multiracial/other individuals. The disparities actually increased for blacks (1.3%) and American Indians or Alaska Natives (2.3%). Across all groups, screening rates were still far short of the goal of reaching 80% screening for the population.

These findings exemplify how the United States is making strides to address the national challenge in CRC screening uptake. May et al⁴ suggest that several factors, including health policy changes, national attention to cancer screening and prevention, and more dedicated efforts to increase screening rates overall and across racial/ethnic groups, contributed to the increases in CRC screening uptake, although the authors admit causation based on these interventions cannot be proven based on this study. May et al⁴ also observe that disparities in screening rates between non-Hispanic whites and other racial/ethnic groups only slightly closed, or even increased, underscoring the challenge of achieving health equity in screening.

Health equity has been defined as achieving the absence of avoidable, unfair, or remediable differences among groups of people, including racial/ethnic groups.^5–9 Specific to CRC screening, we support the concept of achieving 80% screening in every community, as has been endorsed by the National Colorectal Cancer Roundtable, as an optimal, achievable metric of health equity. The work by May et al⁴ suggests that current interventions, including ACA, although likely to lead to some continued incremental gains in screening for all groups, are unlikely to achieve health equity in CRC screening. We postulate achieving health equity will require going beyond the largely “one size fits all” approach that typifies national policies such as the ACA, which seem to be necessary, but insufficient to achieve health equity.

Promising interventions with potential to help achieve health equity in screening for racial/ethnic minority groups exist. Evidence-based strategies for improving screening include mailed outreach offering fecal immunochemical test, offering more than just 1 screening option, culturally tailored patient navigation, 1-on-1 education, and patient and clinician reminders, with many having been tested in racial/ethnic minority groups.^10–19 These interventions seem to be most successful when implemented as multiple, rather than single components.²⁰

Revisiting the findings of May et al⁴ emphasizes that the commitment to investing in interventions to achieve health equity in CRC screening will need to be robust (Figure 1). In 2008 (pre-ACA), the screening rate was 63.9% for whites and ranged from 44.7% to 60.6% for racial/ethnic minorities. In 2016, the increase in screening (potentially attributable to ACA and other national trends) increased screening by 6.5% for whites, and by a range of 4.2% to 12.1% for racial/ ethnic minorities. To achieve a future state of 80% screening across all groups, interventions need to be capable of increasing screening by 9.6% for whites, and by a range of 11% to 26.6% for racial/ethnic minorities. The substantially larger gaps between current and target screening rates for racial/ethnic groups underscore that increasing screening for racial/ethnic groups requires a substantial dedication of resources to implementing promising interventions that have been proven to increase screening rates for racial/ ethnic groups. These investments need to go beyond admittedly necessary, but insufficient national policies, such as the ACA. Investment in developing novel interventions focused on addressing screening disparities is also required. The only alternative is to accept inequality in CRC screening, and miss the opportunity to optimize early detection and prevention of CRC across all racial/ethnic groups.²¹

Figure 1.

Progress toward achieving equity in colorectal cancer screening across racial/ethnic groups in the United States. Data from May et al⁴ demonstrate pre-Patient Protection and Affordable Care Act variation in screening rates across racial/ ethnic groups, with rates consistently lower for non-Hispanic whites compared with other groups. After implementation of ACA in 2010, screening rates improved across all racial/ethnic groups between 2008 and 2016. However, disparities between non-Hispanic whites and racial/ethnic groups persisted, and even got worse for some groups. The range of remaining gaps between current rates of screening and achieving equity in screening, defined as reaching 80% screening in every community, is much larger for racial/ethnic minorities (11.0%−26.6%) compared with whites (9.6%). These data suggest that substantial investments need to be made to target implementation of evidence-based interventions for achieving health equity in CRC screening. AI, American Indians; AN, Alaska Natives; NH, Native Hawaiian; PI, Pacific Islanders.