Paul Shao, MD, MS1, Aileen Bui, MD1, Hui Jia, MD2, Felix Leung, MD, FACG3
1David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA; 2VA Greater Los Angeles Healthcare System, North Hills, CA; 3Sepulveda Ambulatory Care Center, VAGLAHS, David Geffen School of Medicine at UCLA, North Hills, CA
Introduction: Adenoma detection rate (ADR) is an important quality indicator for colonoscopy. Interval cancer (IC) is associated with low ADR. Every 1% increase in ADR is associated with a 3% and 5% reduction of the risk of IC and fatal IC, respectively. Water exchange (WE) colonoscopy is considered the best insertion method for improving ADR when compared with water immersion and air insufflation (AI). Attachment devices such as cap and Endocuff also improve ADR. We assessed the effectiveness of improving ADR between WE, cap and Endocuff colonoscopy by indirect comparison with AI as the common comparator.
Methods: A literature search was done to identify all relevant RCTs comparing WE, cap and Endocuff with AI colonoscopy published since 2000 as full text in English and including ADR among the outcomes. EMBASE, Medline, SCOPUS, and Cochrane Library were searched systematically for all RCTs that included the following terms in their titles, abstracts, or keyword lists: colonoscopy, and water exchange, cap, or Endocuff. Two investigators screened the articles manually and separately. The results were compared; and a discussion was held with a third investigator to resolve any discrepancies.
Results: A total of 1,453 articles resulted from initial keywords search. 37 articles were identified based on titles and abstracts alone. After thorough review of full texts, and discussion between the investigators, 21 RCTs were included in the analysis. A total of 16,572 subjects underwent AI, WE, cap (CC) or Endocuff (EC) colonoscopy. ADR of WE, CC, and EC were compared to AI. Table 1 shows that there is a significant difference in ADR between AI and WE (24.2%, 30.8%, p=0.0001). ADR in AI and EC were significantly different (41.7%, 48.0%, p=0.0001). No significant difference in ADR exists between AI and CC, (36.8%, 36.6%, p=0.92). ADR as a percentage change of AI in WE, EC and CC were 27.4%, 15.1% and -0.42%, respectively. We found that WE and EC significantly improved ADR while CC does not significantly change ADR. Compared to EC and CC, WE has a higher percentage increase in ADR. This greater increase in ADR by WE may be related to the low ADR in the AI group.
Discussion: The impact of the study method in enhancing overall ADR is more prominent with the WE method, especially in patient cohort with lower ADR.
Citation: Paul Shao, MD, MS; Aileen Bui, MD; Hui Jia, MD; Felix Leung, MD, FACG. P0363 - IMPACT OF WATER EXCHANGE, CAP AND ENDOCUFF ON ADENOMA DETECTION RATE: AN INDIRECT COMPARISON WITH AIR INSUFFLATION AS THE COMMON COMPARATOR. Program No. P0363. ACG 2019 Annual Scientific Meeting Abstracts. San Antonio, Texas: American College of Gastroenterology.