Social Determinants of Health: Are Colonoscopies Always Fit for Duty?

ABSTRACT

Objectives: Colorectal cancer (CRC) screening rates continue to be low among safety-net populations. We sought to elucidate the impact of social determinants of health (SDOH) on the noncompletion of fecal immunochemical tests (FITs) and colonoscopies at the Providence Community Health Centers (PCHC).

Study Design: This was a retrospective cohort review of PCHC patients with associated SDOH profiles between December 1, 2018, and December 1, 2019.

Methods: We analyzed fulfilled and unfulfilled CRC screening orders (FITs and colonoscopies) and examined associations and odds ratios between order noncompletion and the presence of SDOH variables. The study sample consisted of a total of 517 orders (fulfilled and unfulfilled; FIT, n = 348; colonoscopy, n = 169).

Results: FITs were completed more often than colonoscopies (81.3% vs 65.7%, respectively; P < .001). Colonoscopy noncompletion was associated with patient-reported social determinants of “housing insecurity/homelessness” (P = .0083) and “living conditions” (P = .048) and staff-reported “behavioral health problem” (P = .048). The presence of housing insecurity/homelessness increased the likelihood of an unfulfilled colonoscopy order (odds ratio, 7.5; 95% CI, 1.3-75.0). Patients who reported any SDOH need had a statistically significant increase in colonoscopy noncompletion (P = .0022), whereas FIT noncompletion was not associated with the presence of SDOH needs (P = .81).

Conclusions: Providers should consider FITs as a strategic real-world modality for patients with SDOH needs.

Am J Manag Care. 2023;29(8):395-401. https://doi.org/10.37765/ajmc.2023.89405

Takeaway Points

We demonstrated an association between the presence of specific social determinants of health (SDOH) and colonoscopy noncompletion. Although colonoscopies are the gold standard modality for colorectal cancer screening, providers should consider fecal immunochemical tests (FITs) as a strategic modality for patients with specific SDOH profiles. Our findings should encourage health care systems across the country to collect SDOH for their patients to better tailor preventive health efforts.

• The collection of SDOH yields actionable information.
• FITs have higher completion rates than colonoscopies.
• Colonoscopy noncompletion is associated with 1 or more SDOH.

Accountable care is a method for passing on a portion of the fiscal risk of poor health outcomes for patients, directly or indirectly, to organizations providing that care. In practice, this means moving from a one-size-fits-most-patients workflow to a series of facilitated parallel patient journeys that deliver different pieces, or intensities, of a “traditional office-based visit” in non–exam room settings, dynamically flexing to what each patient needs at that time.

Federally qualified health centers (FQHCs) are bound by Uniform Data System quality metrics and typically need to layer on additional measures to participate in accountable care. Measures to create reliability, and the reliability of processes in health care, are often poor, particularly when time pressure exists¹—time pressure that fee-for-service invariably causes in paying for processes instead of outcomes. Our FQHC, the Providence Community Health Centers (PCHC), has roughly 35,000 attributed Medicaid lives in a shared-savings contract, which constitutes approximately 65% of our business. In ensuring that we excel at quality measures and succeed in a value-based contract, PCHC in Rhode Island actively undertake quality improvement initiatives. Our goal in this instance is to improve colorectal cancer (CRC) screening through assessing, understanding, and mitigating the impact of our patients’ social determinants of health (SDOH) needs.

The US Preventive Services Task Force (USPSTF) recommends screening for CRC in all adults aged 50 to 75 years (grade A) and all adults aged 45 to 49 years (grade B). CRC screening modalities include direct visualization tests, such as colonoscopies, and stool-based tests, such as fecal immunochemical tests (FITs). Colonoscopies and FITs differ drastically in terms of screening frequency (every 10 years vs every year, respectively) and preparation. Whereas a colonoscopy requires bowel preparation, transportation to and from examination, and sedation, a FIT can be completed with a single stool sample.²

The USPSTF evaluated FITs as saving 292 life-years per 1000 individuals screened if starting screening at age 50 years compared with colonoscopies at 310 life-years.² This difference in a perfect world is real; however, real-world data show that half of colonoscopies ordered are never scheduled and that only 40% of patients are made aware of alternatives.³ The USPSTF also concluded that there are 40% more harms associated with colonoscopies, albeit at only 14 per 1000 procedures. Pulmonary, cardiovascular, and cerebrovascular complications related to colonoscopies have been associated with older age, increasing comorbidity, lower income, and government or self-pay insurance; the last is prevalent in FQHCs.⁴ Black race, low income, and public insurance have been associated with postcolonoscopy adverse events,⁵ and these characteristics are notably enriched in many Medicaid populations. Meanwhile, Black adults have the highest incidence of and mortality from CRC.⁶

Safety-net populations, consisting of Medicaid-insured and uninsured patients, have the lowest CRC screening rates compared with privately and commercially insured patients.⁷ Gupta et al highlighted many multilevel challenges that affect screening, from the level of the individual patient to providers/teams and national policy.⁸ On the individual level, personal attitudes, such as disgust and stigmas, have been shown to affect completion rates.^9,10 From a structural perspective, patient access to CRC screening in general is inextricably linked to SDOH.¹¹

When outcomes, quality, and cost are commingled with actual patient preference and adherence, a test that is “less perfect”—but more achievable by patients—could be the best, most efficacious choice. If that test also decreases the procedural burden in the local system of care such that those who need procedures receive more timely care, an additional societal benefit is achieved, as colonoscopy occurring 10 or more months after an abnormal FIT result has been associated with a higher risk of CRC and more advanced-stage disease at the time of diagnosis.¹²

To improve our performance in CRC screening, we analyzed FIT and colonoscopy data from our electronic health record (EHR) system (Intergy by Greenway), without making any changes in clinical practice other than beginning to systematically collect SDOH and assist patients with accessing resources. Our study compares the associations between the presence of 9 SDOH categories (8 self-reported, 1 staff-reported) and colonoscopy and FIT noncompletion. Previous studies have compared patient adherence to colonoscopy vs FIT with mixed findings.^13-15 Published FIT completion rates, including from studies that examined outreach programs and mailed-in FIT programs, range from 28% to 53.7%, whereas screening colonoscopy completion rates can range from 24.6% to 38.4%.^13-17 In the FQHC setting, Bharti et al reported a diagnostic colonoscopy completion rate of 44% in patients with abnormal FIT results.¹⁸ An examination of the impact of SDOH on modality completion is lacking and likely to reveal practical, impactful solutions. Whereas other studies have illuminated the association between demographic factors and CRC screening uptake,^17,19 we did not draw associations between demographic factors and our 9 unique SDOH categories; rather, we investigated the association between SDOH needs and colonoscopy and FIT noncompletion.

METHODS

Study Sample and Measures

A flow chart depicting the following sample selection is provided in the Figure. We generated a report from our EHR consisting of all CRC screening orders (colonoscopies or FITs) for PCHC patients between December 1, 2018, and December 1, 2019 (n = 3115). We isolated orders with associated SDOH profiles (n = 705), and we removed voided orders (n = 6). Of the 699 orders remaining, 382 were FIT orders and 317 were colonoscopy orders. The Intergy report indicated that 283 of 382 FIT orders and 111 of 317 colonoscopy orders were completed (“fulfilled”). Conversely, 99 of 382 FIT orders and 206 of 317 colonoscopy orders were uncompleted (“unfulfilled”). To exclude unfulfilled orders placed within the December 1, 2018, to December 1, 2019, window that were likely to be filled, we further defined “unfulfilled” orders as FITs not completed within 8 weeks of the order date and colonoscopies not completed within 6 months of the order date. These time frames were selected to account for ease of completion. FITs can be completed same day in clinic, at home and dropped off at clinic, or during a routine follow-up appointment. Colonoscopy orders require advanced scheduling, and appointment availability is variable. It is reasonable to assume that 8 weeks for FIT and 6 months for colonoscopy are ample time frames for completion. Moreover, the 6-month colonoscopy window allows for cases in which the first appointment might be unintentionally missed or canceled. Therein, we removed unfulfilled FIT orders (n = 34) placed within 8 weeks of the December 1, 2019, study window cutoff (orders placed between October 6, 2019, and December 1, 2019) and unfulfilled colonoscopy orders (n = 148) placed within 6 months of the study window cutoff (orders placed between June 1, 2019, and December 1, 2019). The final sample consisted of a total of 517 orders (fulfilled and unfulfilled; FIT: n = 348; colonoscopy: n = 169).

We compared SDOH profiles from patients with unfulfilled orders with SDOH profiles from patients with fulfilled orders. SDOH profiles were previously collected in clinic using a modified Health Leads toolkit consisting of 8 questions to which a patient or a parent/caregiver responded. This modified toolkit is adapted from the Health Leads 2018 Social Needs Screening toolkit, which is based on clinically validated guidelines. Interpreters were provided for non-English speakers. Providers confirmed the presence of comorbid behavioral health diagnoses, which constituted a ninth variable. The 9 SDOH categories as they appear in this report are defined in Table 1. As a locally designed quality improvement project, this work did not meet the US federal definition of human subjects research and therefore did not necessitate institutional review board or human research protection program review.

We examined 3 groups: (1) total (colonoscopy + FIT; n = 517; unfulfilled, n = 123; fulfilled, n = 394), (2) FIT (n = 348; unfulfilled, n = 65; fulfilled, n = 283), and (3) colonoscopy (n = 169; unfulfilled, n = 58; fulfilled, n = 111). Details are shown in Table 1.

Sample Characteristics

Age, biological sex, and primary language (English vs non-English) were examined across both the patients without SDOH profiles (n = 2410), who were excluded from the study, and the patients with SDOH profiles (n = 705). These same characteristics were examined across the FIT and colonoscopy groups of the final patient sample (Table 2) and were additionally stratified by SDOH (Table 3). Non-English languages, in order of most to least commonly encountered, included Spanish/Castilian, Cambodian (Khmer), Portuguese, Laotian, Haitian/Haitian Creole, Cree, Arabic, Sango, and Russian.

Statistical Analysis

Associations, t tests, analysis of variance, and odds ratios (ORs) were performed using Stata software (StataCorp LLC). Associations were analyzed using Pearson χ² (if ƒ ≥ 5 observations per cell) and Fisher exact (if ƒ < 5 observations per cell) tests. The α level was set at P ≤ .05.

RESULTS

Our data set yielded a 76.2% fulfillment rate of CRC screening orders (FIT orders or colonoscopy orders). FIT orders were fulfilled more frequently than colonoscopy orders (81.3% [283/348] vs 65.7% [111/169], respectively; P < .001).

Effect of SDOH on CRC Screening

The presence of at least 1 SDOH was reported in 23.6% (29/123) and 19.3% (76/394) of unfulfilled and fulfilled orders, respectively. There were no significant differences in the proportions of unfulfilled orders with at least 1 SDOH compared with fulfilled orders with at least 1 SDOH in either the total (OR, 1.3; 95% CI, 0.8-2.1; P = .30) or FIT (OR, 1.1; 95% CI, 0.5-2.1; P = .81) study groups. However, of patients with unfulfilled colonoscopies, 20.7% (12/58) screened positive for at least 1 SDOH; in contrast, of patients with fulfilled colonoscopies, 5.4% (6/111) screened positive for at least 1 SDOH (OR, 4.6; 95% CI, 1.5-16.0; P = .0022) (Table 1). In our data set, colonoscopies were ordered for 17.1% (18/105) of patients with at least 1 SDOH compared with 36.7% (151/412) of patients without any SDOH needs (OR, 0.38; 95% CI, 0.20-0.64; P = .0001).

Frequencies of Individual SDOH

In general, SDOH frequencies were higher in patients with unfulfilled orders compared with those with fulfilled orders in all 3 groups. There were no significant differences between the frequencies of individual SDOH categories in fulfilled orders compared with unfulfilled orders for the total or FIT study groups. However, in the colonoscopy group, unfulfilled orders were associated with a higher frequency of “behavioral health (BH) problem” (P = .048), “housing insecurity/homelessness” (P = .0083), and “living conditions” (P = .048). The presence of housing insecurity/homelessness increased the likelihood of an unfulfilled colonoscopy order (OR, 7.5; 95% CI, 1.3-75.0), whereas BH problem (OR, 5.1; 95% CI, 0.80-55.0) and living conditions (OR, 8.1; 95% CI, 0.8-405.0) did not (Table 1).

DISCUSSION

The data demonstrate completion rates of 81.3% for FITs and 65.7% for colonoscopies in PCHC patients for whom CRC screening was ordered. These completion rates exceed many of the aforementioned rates published in the literature. The disparity we observed in FIT and colonoscopy completion rates may be related to the statistically significant differences in frequencies of BH problem (P = .048), living conditions (P = .048), and housing insecurity/homelessness (P = .008) in patients with unfulfilled colonoscopy orders compared with fulfilled orders (Table 1). Despite the statistically significant differences in frequencies in these 3 SDOH categories among patients with unfulfilled colonoscopy orders compared with fulfilled orders, only housing insecurity/homelessness yielded a statistically significant OR in our data set.

The presence of housing insecurity/homelessness increased the likelihood of colonoscopy noncompletion (OR, 7.5; 95% CI, 1.3-75.0). This finding does not come as a surprise given the degree of bowel preparation that is required for colonoscopy screening, day-of-procedure requirements for transportation and accompaniment, and the need to take off a full day of work. Previous studies have observed a linkage between domicile inaccessibility and CRC screening adherence; Asgary et al found poor adherence to colonoscopy among individuals experiencing homelessness compared with domiciled patients in New York City, likely due to the lack of privacy and comfort for completing procedure preparation.²⁰ PCHC patients with inconsistent housing may experience comparable difficulties adhering to colonoscopy preparation.

Although living conditions and BH problem did not achieve significant ORs for noncompletion, they reached significance for association and are mechanistically consistent with worsening the completion rate of a colonoscopy procedure. These variables have a much less, if any, clear mechanism for affecting FIT testing.

Whereas adverse living conditions may affect colonoscopy completion in a fashion similar to that of the housing insecurity/homelessness category, a BH problem can produce multiple barriers to the completion of a colonoscopy in terms of preparation and missing the procedure. Yang et al showed that among studies evaluating patients undergoing colonoscopy, 13% to 37% of patients felt anxious about bowel preparation, and 53% of patients were anxious about procedure complications.²¹ BH conditions that predispose patients to anxiety or demotivation could logically result in decreased adherence to colonoscopy preparation and produce increased rates of colonoscopy noncompletion.

The statistically significant difference in fulfillment rates of FIT compared with colonoscopy in our patient population with variable SDOH and behavioral health burdens begs the question as to whether certain patient populations should simply be offered a FIT first instead of a colonoscopy. The argument in favor of colonoscopy as the gold standard for CRC screening is largely entrenched in the modality’s sensitivity and specificity,²² in its utility as both a screening and diagnostic tool, and in its favorable screening frequency. FITs trade higher sensitivity for lower specificity, yielding false-positive results from comorbidities such as hemorrhoids and prompting follow-up colonoscopy.²³ What is not entertained is the real-world completion rate of colonoscopy orders compared with other screening modalities. The significant colonoscopy noncompletion rate that we observed highlights a tangible discordance between provider expectation and patient ability that warrants consideration by ordering clinicians.

Our data suggest how a FIT-first model could provide broader patient population surveillance. This model could concomitantly reduce the procedural burden that the colonoscopy-first model places on local health systems. Annual FIT starting at age 50 years reduces the mean estimate of lifetime colonoscopy by 56.8%,² resulting in a decrease in procedural burden and an attendant increase in colonoscopy access for vulnerable populations. Patients with positive FIT results undergo diagnostic colonoscopy, and research has shown that Medicaid patients are less likely than those with commercial insurance to complete a colonoscopy following a positive FIT.^12,24 However, our study sheds light on a few of the knowable SDOH needs that deleteriously affect colonoscopy completion—factors that we expect could be mitigated through patient navigation efforts.²⁵ Reducing colonoscopy burden through a FIT-first model could make available additional procedural capacity and additional resources for facilitating diagnostic colonoscopy completion for patients with positive FIT results.

We found that colonoscopies were ordered for 17.1% (18/105) of our patients with at least 1 SDOH compared with 36.7% (151/412) of patients without any SDOH insecurities. Although these data suggest an effort on behalf of the patient and provider to select the most appropriate screening modality, 66.7% (12/18) of patients with at least 1 SDOH who received an order for a colonoscopy could not complete their order. Additional attention to SDOH is needed to improve completion rates. In comparable patient populations, providers should consider SDOH (including behavioral health conditions) in conjunction with patient preference when choosing the most appropriate screening modality. The likelihood of colonoscopy noncompletion when a patient screens positive for at least 1 SDOH should at least be evaluated in terms of the increased probability of screening and diagnostic delay.²⁶

Limitations

With regard to study weaknesses, performing a multivariate regression as opposed to a categorical association would aid in elucidating the multifaceted causality of SDOH categories on CRC screening noncompletion. However, given the sample size in our data for some SDOH categories, multivariate analysis would have been underpowered to detect clinically important correlations. This low sample size likely contributed to the discrepancy between association significance and OR significance in the living conditions and BH problem categories. Moreover, the BH problem category would benefit from more robust, continuous variables, such as data from insurance claims or from Patient Health Questionnaire-9. An analysis of age, sex, and primary language between the FIT and colonoscopy groups did not yield statistically significant differences. However, study sample race/ethnicity data and insurance status were not available for inclusion in this analysis. Although our clinic benefits from robust interpreter services, implicit bias could be a confounder that affects which patients receive orders for FIT vs colonoscopy.

CONCLUSIONS

The adage that “the best test is the one that gets done”⁸ is paramount in tailoring preventive medicine efforts. This was a descriptive study upon which we will base future data-driven initiatives that align with our patients’ ability to comply with the best test that they are willing to complete. The data demonstrate the importance of collecting SDOH profiles from patient populations and the clear impact of SDOH on CRC screening noncompletion. Providers managing safety-net populations should consider ordering FITs as a more effective modality in real-world situations for all eligible patients with at least 1 SDOH, and in particular for patients screening positive for housing insecurity/homelessness, living conditions, and/or a BH problem.

With regard to next steps, a future study in which we contact PCHC patients to inquire about the specific reasons for colonoscopy noncompletion could open the door for the implementation of interventions such as peer coaches or patient navigators, which have been shown to increase screening colonoscopy adherence in urban populations.²⁷ This type of quality improvement project, in which we illuminate the impact of SDOH on screening noncompletion, can and will be extended to other preventive medicine efforts in our clinic.

Author Affiliations: The Warren Alpert Medical School of Brown University (BKS), Providence, RI; Providence Community Health Centers (JIG), Providence, RI; Program in Biology, Brown University (KAM), Providence, RI.

Source of Funding: None.

Author Disclosures: The authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (BKS, JIG); acquisition of data (BKS, JIG); analysis and interpretation of data (BKS, KAM); drafting of the manuscript (BKS, JIG, KAM); critical revision of the manuscript for important intellectual content (BKS, JIG, KAM); statistical analysis (BKS, KAM); provision of patients or study materials (JIG); administrative, technical, or logistic support (JIG); and supervision (JIG).

Address Correspondence to: Benjamin K. Stone, MSc, Warren Alpert Medical School of Brown University, 222 Richmond St, Providence, RI 02903. Email: benjamin_stone@brown.edu.

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