Abstract 4238: Impact of diabetes mellitus on adenoma detection rates in three disparate institutions
Authors: David Yakira , Ottaviano Lorenzo , Iqbal Sadat , Lung Brandon , Likhtshtegyn Michelle , Kumar Samir , Li Ellen , Martello-Rooney Laura , Vignesh Shivakumar , Miller Joshua , Grossman Evan 
Published: August 2018

Background: Racial disparities persist in the incidence and mortality of colorectal cancer despite the availability of screening tools. Adenoma detection rates have been associated with diabetes in some studies. This study seeks to evaluate the effect of diabetes mellitus on adenoma detection rates (ADR) in initial screening colonoscopies performed at three distinct institutions.

Methods: A retrospective chart review was performed on all initial average risk screening colonoscopies performed on patients between 45-75 years at an Urban Safety Net Hospital (USNH), an Urban University Hospital (UUH) and a Suburban University Hospital (SUH) from January 1st to December 30th 2012 to coordinate existing databases at the three institutions. Patients were excluded if they had a history of colon cancer, polyps, alarm symptoms, or if the current colonoscopy was incomplete or had poor bowel prep. Data points collected included sex, age, race, insurance, BMI, smoking status, diabetic status and attending provider. Univariate analysis was performed comparing ADRs between the three institutions using Graph Pad Prism. Further comparisons were made between current smoking and diabetes status with ADR.

Results: There were a total of 2225 initial screening colonoscopies (SUH, n =647; UUH, n = 444; USNH, n = 1134) excluding 135 incomplete and/or poor prep colonoscopies (SUH, n = 34; UUH, n = 50; USNH, n = 51). USNH and UUH patients were more likely to be African-American (93% and 88% vs 7%, p&lt;0.0001) and diabetic (29.7 and 29.8% vs 12%, p &lt;0.0001) than the SUH patients. UUH and SUH patients were more likely to be male (39% and 40% vs. 32%, p&lt;0.0001), more likely to be current smokers than the USNH patients (11.9% and 12.8% vs 5.8%, p&lt;0.0001), and were less likely to be uninsured (7% and 3% vs 43%, p&lt;0.0001). In 2012 the ADR was significantly lower in patients at the USNH compared to both the UUH and SUH( 17% vs 30% and 26%, p&lt;0.0001), but with the institution of ADR monitoring at the USNH, the ADR has since increased to 29% in 2017. Across all three institutions diabetics were noted to have higher ADRs (26% vs 18%, OR 1.6 95% CI 1.3-2.0, p&lt;0.0001) and current smokers were noted to have higher ADRs (30% vs. 20%, OR 1.8 95% CI 1.3-2.4, p = 0.001)

Discussion: Diabetes and current smoking are associated with increased ADR across all three institutions despite differences in race and baseline ADR. Patients should be counseled on the increased risk associated with diabetes and smoking. Initiatives should be implemented to insure improved screening rates for adenomas among diabetics and also to screen for diabetes so that interventions can be made early to reduce the impact of diabetes on colon cancer risk. Further prospective studies are needed to validate these findings.

Citation Format: Yakira David, Lorenzo Ottaviano, Sadat Iqbal, Brandon Lung, Michelle Likhtshtegyn, Samir Kumar, Ellen Li, Laura Martello-Rooney, Shivakumar Vignesh, Joshua Miller, Evan Grossman. Impact of diabetes mellitus on adenoma detection rates in three disparate institutions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4238.