Impact of type 2 diabetes on adenoma detection in screening colonoscopies performed in disparate populations

Abstract

BACKGROUND The Black/African Ancestry (AA) population has a higher prevalence of type 2 diabetes mellitus (T2DM) and a higher incidence and mortality rate for colorectal cancer (CRC) than all other races in the United States. T2DM has been shown to increase adenoma risk in predominantly white/European ancestry (EA) populations, but the effect of T2DM on adenoma risk in Black/AA individuals is less clear. We hypothesize that T2DM has a significant effect on adenoma risk in a predominantly Black/AA population. AIM To investigate the effect of T2DM and race on the adenoma detection rate (ADR) in screening colonoscopies in two disparate populations. METHODS A retrospective cohort study was conducted on ADR during index screening colonoscopies (age 45-75) performed at an urban public hospital serving a predominantly Black/AA population (92%) (2017-2018, n = 1606). Clinical metadata collected included basic demographics, insurance, body mass index (BMI), family history of CRC, smoking, diabetes diagnosis, and aspirin use. This dataset was combined with a recently reported parallel retrospective cohort data set collected at a suburban university hospital serving a predominantly White/EA population (87%) (2012-2015, n = 2882). RESULTS The ADR was higher in T2DM patients than in patients without T2DM or prediabetes (35.2% vs 27.9%, P = 0.0166, n = 981) at the urban public hospital. Multivariable analysis of the combined datasets showed that T2DM [odds ratio (OR) = 1.29, 95% confidence interval (CI): 1.08-1.55, P = 0.0049], smoking (current vs never OR = 1.47, 95%CI: 1.18-1.82, current vs past OR = 1.32, 95%CI: 1.02-1.70, P = 0.0026 ) , older age (OR = 1.05 per year, 95%CI: 1.04-1.06, P < 0.0001), higher BMI (OR = 1.02 per unit, 95%CI: 1.01-1.03, P = 0.0003), and male sex (OR = 1.87, 95%CI: 1.62-2.15, P < 0.0001 ) were associated with increased ADR in the combined datasets, but race, aspirin use and insurance were not. CONCLUSION T2DM, but not race, is significantly associated with increased ADR on index screening colonoscopy while controlling for other factors.

Symptomatic Colorectal Cancer Is Associated With Stage IV Diagnosis in Two Disparate Populations

“…Clinical metadata were manually collected on each patient using electronic medical records (EMRs) at the two hospitals. Datapoints recorded included: age at the time of pathologic diagnosis of CRC; sex (Male, Female); race (White/EA, Black/AA, Asian, Other); Hispanic ethnicity; insurance (Commercial, Medicare, Medicaid, Self-pay); body mass index (BMI) (kg/m2); tobacco exposure (current within one year, past use greater than one year, never); Family history of first degree relative with CRC; History of screening colonoscopy prior to diagnosis (Age < 50 y, Age > 80 y, yes, no); Interval CRC defined as diagnosis sometime after a normal screening colonoscopy (yes, diagnosis made within recommended interval for repeat surveillance or screening colonoscopy; no; unknown); Anatomic location of CRC (right or transverse colon to cecum, left or splenic flexure to sigmoid colon, rectum); CRC stage at diagnosis (0-4); and Surgical resection (yes, no), as previously described [5,7]. Patients were phenotyped as diabetic if this diagnosis was in the EMR or if a recent hemoglobin A1c (HbA1c) was ≥ 6.5% [8].…”

“…Initial chart review of procedures performed in 2012 revealed low average adenoma detection rates in screening colonoscopies performed by some operators at one institution [ 7 ]. After intense physician feedback, the average adenoma detection rates increased to above national levels at both institutions by 2017 [ 5 ].…”

“…Associated racial differences in insurance status may affect access to quality CRC screening procedures. Associated racial differences in the prevalence of smoking, obesity, and diabetes mellitus could also contribute to Black/AA CRC risk [3][4][5][6]. Understanding the contributions of these factors is important for designing the most effective approaches towards reducing CRC incidence and mortality risk in the Black/AA populations.…”