Authors: Sara Myers (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts), Elizabeth S. Davis (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts), Olivia A. Sacks (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts), Jeffrey A. Franks (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts), Jennifer S. Davids (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts), Kelly M. Kenzik (1Department of Surgery, Boston Medical Center, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts; 2Sloane Epidemiology Center, Boston University, Boston, Massachusetts)
Categories: Article, Cancer screening, Colonoscopy, Colorectal cancer screening, Disparities, USPSTF
Source: Diseases of the colon and rectum
Authors: Sara Myers, Elizabeth S. Davis, Olivia A. Sacks, Jeffrey A. Franks, Jennifer S. Davids, Kelly M. Kenzik
Colorectal cancer screening lowers mortality, and in 2021, the United States Preventive Services Task Force lowered the recommended age to start colorectal cancer screening for average-risk adults from 50 to 45. However, social and structural factors impact access to screening, and sociodemographic disparities in uptake of the recommendation to begin colorectal cancer screening at age 45 has not been studied among the general population.
Examine disparities in uptake of the 2021 United States Preventive Services Task Force recommendation to start colorectal cancer screening at age 45.
Utilizing 2022 and 2023 Behavioral Risk Factor Surveillance System data, we examined factors associated with colorectal cancer screening using multivariable logistic regression models.
Data from the Behavioral Risk Factor Surveillance System national phone survey.
Adults aged 45–49.
Colorectal cancer screening.
Higher proportions of people with low-income, limited education, no health insurance, and rural residence were unscreened. Uninsured individuals had the lowest odds of undergoing screening (OR = 0.48, 95% CI= 0.37–0.63). Among insured people, low-income (OR = 0.83, 95% CI = 0.73–0.93) and low-education (OR = 0.69, 95% CI = 0.51–0.94) individuals had lower odds of screening; rural uninsured individuals had lower odds of screening than their urban uninsured counterparts (OR = 0.57, 95% CI = 0.37–0.89).
We could not identify individuals with polyps or family histories of hereditary cancer syndromes who would be recommended for early screening regardless of the 2021 guidelines.
Sociodemographic disparities exist in uptake of the 2021 United States Preventive Services Task Force recommendation to start colorectal cancer screening at age 45. Uninsured people had the lowest odds of screening, and uninsured rural individuals had lower odds of screening than their uninsured urban counterparts. Insured low-income and low-education individuals had lower odds of accessing colorectal cancer screening than their higher-income and higher-educated counterparts. Expanding insurance coverage among adults aged 45–49 may increase access to colorectal cancer screening. See Video Abstract.
Colorectal cancer (CRC) is the second leading cause of cancer-related death in the United States (US). CRC incidence and mortality among individuals younger than 50 have increased over the last 20 years, with 13% of new CRC cases diagnosed in this younger population.^1^ In contrast, CRC incidence and mortality have decreased among those 50 and older, largely due to screening.^2^ CRC screening with any modality (e.g., endoscopy, virtual colonoscopy, fecal immunohistochemical testing [FIT]) is associated with lower CRC mortality among all ages.^3^ In response, in 2021, the United States Preventive Services Task Force (USPSTF) lowered the recommended age to start CRC screening for average-risk adults from 50 to 45 years old.^3^ While this recommendation applies to all adults regardless of insurance status, the recommendation was graded “B,” mandating all insurers to cover CRC screening starting at age 45 with no out-of-pocket patient costs.^4^ Despite insurance coverage, social and structural factors, such as race, ethnicity, and socioeconomic status, impact access to CRC screening.^5^ Disparities in CRC screening are associated with worse CRC outcomes among minority populations, including presentation at later stages of disease and higher mortality.^5^
Sociodemographic factors that impact access to CRC screening among individuals aged 45–49 have not been quantified and require further study in order to address disparities. Social determinants of health (SDoH), the conditions in which people live, work, and learn, may contribute to disparities in access to screening among marginalized people, including low-income, uninsured, rural, and racial and ethnic minority populations.^6^ Identifying and addressing screening disparities may help reduce inequities in CRC outcomes, and uptake of the USPSTF recommendation to begin CRC screening at age 45 has not been studied among the general population. We utilized nationally representative survey data to examine the effects of SDoH on CRC screening uptake among individuals aged 45–49 years old.
We utilized the Centers for Disease Control and Prevention’s (CDC) Behavioral Risk Factor Surveillance System (BRFSS), an ongoing, nationally representative, telephone-based survey of non-institutionalized adults ≥18 years of age. BRFSS is conducted yearly in all 50 US states, the District of Columbia, and three US territories through random digit dialing techniques and completes over 400,000 interviews annually.^7^ Questions focus on health-related behaviors, access to healthcare, and use of preventive care including cancer screening. BRFSS data is used by public health agencies at local, state, and federal levels to monitor prevalence of diseases and help implement disease prevention programs and is also commonly used by health services researchers.^7–9^ BRFSS uses survey weights to ensure that results are representative of the entire US population rather than just the sample population sample. Survey weights adjust for probability of selection, nonresponse, and demographic variables (age, race/ethnicity, sex, geographic region within states, education, marital status, home ownership, and type of telephone ownership [landline and/or cellular]).^10^ Survey weights for 2021 and 2022 were combined and adjusted proportional to sample size in each year to calculate the survey weights used in this study.^10^
In order to capture the population targeted by the 2021 USPSTF CRC screening recommendations, we evaluated individuals aged 45–49 years with no history of colon or rectal cancers. CRC screening was captured with the following “Colonoscopy and sigmoidoscopy are exams to check for colon cancer. Have you ever had either of these exams?” and “Have you ever had any other kind of test for colorectal cancer, such as virtual colonoscopy, CT colonography, blood stool test, FIT DNA, or Cologuard test?” Those who had ever undergone any CRC screening test were designated as having been screened. We examined and categorized sociodemographic data including sex, race (White, non-White), annual household income (<50,000–100,000, >$100,000), education (+/− graduated high school), rural-urban status, health insurance coverage (any, none), medical-related financial challenges (yes, no), and transportation challenges (prior 12 months; yes, no). Financial challenges were captured with the question, “Was there a time in the past 12 months when you needed to see a doctor but could not because you could not afford it?” and transportation challenges were captured with the question, “During the past 12 months has a lack of reliable transportation kept you from medical appointments, meetings, work, or from getting things needed for daily living?” We compared characteristics of individuals who were screened to those who were not screened using chi-square tests. All analyses were conducted using survey weights as recommended by BRFSS.
We used multivariable logistic regression to assess factors associated with CRC screening. Models included sex (ref. male), race (White (ref) vs non-White), income (≥50,000–100,000 vs <$50,000), education (high-school diploma (ref) vs without), and rurality (urban (ref) vs rural). Models were then stratified by insurance status (any coverage vs none); although the USPSTF recommendation applies to all adults 45+ regardless of insurance status, the insured and uninsured populations are different with regards to accessing screening. Analyses were conducted in SAS v9.4 (Cary, NC) using SAS survey procedures to incorporate BRFSS survey weights.^11^
We compared CRC screening rates between adults aged 45–49 and those 50–64, 65–74, and 75+ years with chi-square analyses; we selected these age groups in order to capture the individuals recently recommended to start screening (45–49), those who are not yet eligible for Medicare (50–64), Medicare-eligible (65–74), and those for whom screening is recommended on an individual basis (75+). We categorized age groups into 45–49 and 50+ for multivariable logistic regression models. Models included sex, race, income, education, rurality, and insurance status, and were then stratified by age group (45–49, 50+) in order to establish whether the association between sociodemographic factors and CRC screening varied between age groups.^12,13^
Among 30,020 individuals between the ages of 45–49 without a personal history of CRC, 32.8% (n = 9,854) underwent CRC screening. Among age groups 50–64, 65–74, and 75+, 68.3% (n = 86,386), 83.4% (n = 80,832), and 79.4% (n = 58,711) of individuals respectively had ever been screened (p < 0.0001 comparing all age groups). Individuals who were aged 45–49, male (p = 0.0425), had incomes <$100,000 (p < 0.0001), did not graduate high school (p < 0.0001), were uninsured (p < 0.0001), could not afford to see a doctor in the last 12 months (p = 0.0091), and those with healthcare-related transportation challenges (p < 0.0001) underwent screening less than their counterparts (Table 1). Rates of screening were not significantly different between White and non-White people (p = 0.0554).
Multivariable logistic regression models revealed lower odds of CRC screening among low-income individuals (<50–100,000 OR = 0.84, 95% CI = 0.74–0.96), those without a high-school diploma (OR = 0.75, 95% CI = 0.57–0.99), and uninsured individuals (OR=0.48, 95%CI=0.37–0.63); odds of screening did not differ by sex, race, or rurality (Fig. 1). However, when stratified by insurance status, uninsured rural individuals had lower odds of CRC screening (OR=0.57, 95% CI = 0.37–0.89), while race, sex, income, and education were not significant. Insured people of lower income (OR=0.83, 95% CI = 0.73–0.93) and without a HS diploma (OR = 0.69, 95% CI = 0.51–0.94) had lower odds of screening, while race, sex, and rurality were not significant (Fig. 2).
In multivariable logistic regression models including age as a covariate, individuals aged 45–49 had lower odds of undergoing screening than those 50+ (OR = 0.14, 95% CI = 0.13–0.15). When models were stratified by age, adults 50+ who were non-White (OR = 0.67, 95% CI = 0.63–0.71), in the lowest income category (<50,000–100,000 for adults 50+.
In this study utilizing survey data representative of the general US population, we found sociodemographic disparities in CRC screening among adults aged 45–49 years, with a screening rate less than half that of adults 50+, suggesting low uptake overall of the 2021 USPSTF recommendation. Specifically, those who were uninsured, low-income, and did not have a high school diploma had lower odds of CRC screening overall. When stratified by insurance status, the rural uninsured were the least likely to undergo screening. This is the first study to evaluate uptake and disparities in implementation of the 2021 USPSTF CRC screening recommendations in the general US population.
We found insurance coverage to be a crucial component of CRC screening, as uninsured adults had less than half the odds of screening compared to the insured. Although this finding may be expected, disparities in screening among uninsured individuals have not been quantified, and this result has important implications given the USPSTF recommendation to start CRC screening at age 45 applies to all individuals, not only those with insurance. A prior study of >10 million Blue Cross Blue Shield (BCBS) beneficiaries identified increased CRC screening among average-risk people aged 45–49 following the 2021 USPSTF recommendations.^14^ However, this study utilized claims data, which excludes the vulnerable uninsured population. Further, a single-site study found a rapid increase in CRC screening orders for patients aged 45–49y following the 2021 recommendations, though over 80% of patients were commercially insured, and publicly insured or uninsured patients had significantly lower odds of having a CRC screening test ordered by their PCP.^15^ As 19% of Americans have Medicaid and 10% are uninsured, CRC screening trends among the privately-insured may not be reflective of the general population.^16^ Our results identify insurance status as a vital modifiable barrier to CRC screening, and policy makers may wish to consider expanding health insurance access to increase CRC screening uptake among the eligible population.
Sociodemographic factors beyond insurance coverage, including income, education, and rurality, were also associated with CRC screening in our population. A study of BCBS beneficiaries found that CRC screening rates following the 2021 USPSTF recommendation were highest among individuals living in high-income and metropolitan areas.^14^ While robust, the study did not examine individual-level SDoH beyond race, rurality, and a composite social deprivation score, which fails to capture nuances of individual social determinants. In addition to race and rurality, we examined income, education, financial hardship, and transportation challenges to characterize specific SDoH associated with CRC screening. We found the unscreened population to have higher proportions of individuals with low incomes, limited education, financial hardship, and healthcare-specific transportation challenges. Although we could not determine whether individuals were aware of screening recommendations, limited education being an independent risk factor for going unscreened suggests low health literacy may have contributed to lower screening rates. While these data identify potential targets for intervention and policy aimed at increasing CRC screening among these marginalized populations, future work should also investigate whether individuals are aware of updated age-based CRC screening recommendations.
Although individuals in the younger age group had one-tenth the odds of screening compared to those 50+, most SDoH associated with screening did not differ between the 45–49yo and the 50+yo groups. However, while race was not significantly associated with screening among adults aged 45–49, non-White individuals 50+ had lower odds of screening. This racial disparity in CRC screening has been established in this older age group, but low screening rates in the 45–49 year old group may explain why we did not detect a difference based on race.^5^
Notably, insurance coverage did not offset the risk associated with being low-income or lacking a HS diploma in our population, as insured individuals with low incomes and without a HS diploma still had lower odds of screening. While CRC screening is covered under the Patient Protection and Affordable Care Act (ACA), there may be “hidden costs” associated with screening.^4,17,18^ Colonoscopies, which are the gold standard CRC screening tests, are usually performed with anesthesia and may require patients to miss work, potentially for both a day of bowel preparation and the day of the colonoscopy.^17,19^ Further, anesthesia associated with the procedure and bowel preparation medications are not covered by all insurers.^18^ Despite the mandate that all insurers cover CRC screening for adults 45 and older with no costs to patients, literature suggests hidden costs may result in insured low-income patients forgoing CRC screening, which we observed in this study.^17,19,20^ Prior work suggests individuals 45–49 are less aware of the range of CRC screening modalities compared to those 50+, but promotion of alternative screening modalities such as FIT may be helpful for such patients, as FIT places lower cost, time, and transportation burdens on patients.^19–21^
Challenges reaching vulnerable populations with survey studies are well established, including those who are undomiciled, non-English speaking, live rurally, and those without access to phones or computers.^22^ Some characteristics of the BRFSS may lead to underrepresentation of marginalized individuals must have a working telephone, and questions are only asked in English and Spanish. For example, our population had higher proportions of urban individuals (87%) compared to the US population (80% urban). This limitation also suggests that CRC screening data underrepresents rural populations, who often face barriers to accessing healthcare and who had lower odds of CRC screening in the present study than urban populations.
Additionally, BRFSS does not ask whether individuals are aware of screening recommendations, making it difficult to assess specific reasons individuals did not undergo screening. Although we excluded individuals with a personal history of colon (n=18) or rectal (n=3) cancer, we could not identify high-risk individuals with polyps or family histories of hereditary cancer syndromes, who would be recommended for screening early regardless of the 2021 USPSTF guidelines. Lastly, the majority of granular data regarding health insurance plan information (i.e. commercial vs Medicaid) was missing.^22^
We identified sociodemographic disparities in uptake of the 2021 USPSTF recommendation to start CRC screening at age 45. Importantly, those with no insurance had the lowest odds of CRC screening, and insured low-income and low-education individuals had lower odds of accessing CRC screening than their higher-income and educated counterparts. Additionally, rural uninsured individuals were less likely to be screened than urban uninsured people. These results suggest that while health insurance coverage is critical for CRC screening uptake, insurance coverage does not fully mitigate the effects of other SDoH. As insurance coverage and other SDoH may compound, expanding insurance coverage may have the spillover effect of increasing screening uptake among rural, low-income, and low-education individuals aged 45–49.