S1563 ACE Inhibitor Use Is Associated With Angioectasias on Video Capsule Endoscopy (VCE) in Patients With Iron Deficiency Anemia

Field: Medicine (Health Sciences)

Introduction: Small bowel bleeding poses a clinical challenge in patients with vascular lesions. Bleeding recurrence after endoscopic therapy is high and medical therapies have limited efficacy. In those with left ventricular assist devices (LVADs), the use of angiotensin converting enzyme inhibitors (ACEi) has been associated with a reduced rate of gastrointestinal bleeding. Conversely, the antiplatelet effects of ACEi have been described thought due to their effects in decreasing platelet aggregation. Our aim was to determine whether ACEi or angiotensin receptor blocker (ARB) therapy had an impact on the rate of positive VCE small bowel findings in those with iron deficiency anemia (IDA). Methods: Data was collected from consecutive inpatient and outpatient VCE examinations performed between January 1, 2009 to March 1, 2018 at a single U.S. tertiary medical center performed for IDA. VCE studies were excluded in those with incomplete small bowel examinations (9) or technical failure (1). Patient demographics, laboratory values, medication use and endoscopic findings were recorded. VCE findings were based on the P0-P2 grading system. The primary outcome of interest was a positive (P2) VCE. Data were analyzed using Wilcoxon rank-sum test for continuous variables and Fischer’s exact test for dichotomous variables. Bivariate logistic regression was performed to identify independent factors predictive of positive VCE. Results: Eighty-two VCE were included in the final analysis. Median age was 67.6 (IQR: 57.1-75.5) years and 38 (46.3%) patients were male. Thirty-seven (45.1%) VCE examinations were positive with the most common finding of angiectasia in 21 (55.3%). Risk factors for positive VCE are listed in Table 1. In univariate analysis, ACEi therapy associated with both positive VCE (P=0.014) and the presence of angiectasia (P=0.021), whereas ARB therapy did not associate with positive VCE. ACEi findings remained significant in bivariate analysis after controlling for cardiac and pulmonary comorbidities. Conclusion: In this single center study the presence of ACEi use was associated with small bowel and/or stomach angiectasias on VCE in univariate analysis and when controlled for cardiac and pulmonary risk factors. Further studies are required to determine the mechanistic impact of ACEi on gastrointestinal bleeding risk such as the reduction in von Willebrand factor or factors that affect platelet aggregation. Table 1. - Univariate predictors of positive video capsule endoscopy in iron deficiency anemia Negative VCE (n = 45) Positive VCE (n =37) P-value Age, years, mean (SD) 63.6 (15.8) 68.6 (9.3) 0.303 Male sex, n (%) 21 (46.7) 17 (46) 1 White race, n (%) 22 (48.9) 20 (54.1) 0.223 Active smoking, n (%) 6 (14) 11 (29.7) 0.105 Outpatient location, n (%) 31 (68.9) 21 (56.8) 0.357 Chronic kidney disease, n (%) 10 (22.2) 13 (35.1) 0.224 Chronic liver disease, n (%) 3 (6.7) 4 (10.8) 0.696 Congestive heart failure, n (%) 10 (22.2) 13 (35.1) 0.224 Diabetes mellitus, n (%) 15 (33.3) 15 (40.5) 0.645 Cardiac valvular disease, n (%) 7 (15.6) 6 (16.2) 1 Coronary artery disease, n (%) 14 (31.1) 14 (37.8) 0.641 Cardiac arrhythmia, n (%) 10 (22.2) 18 (48.7) 0.019 Chronic lung disease, n (%) 10 (22.2) 13 (35.1) 0.224 Left ventricular assist device, n (%) 2 (4.4) 2 (5.4) 1 Blood transfusion in the preceding 4 weeks, n (%) 17 (37.8) 16 (43.2) 0.656 Aspirin, n (%) 20 (44.4) 14 (37.8) 0.654 Thienopyridine, n (%) 3 (6.7) 2 (5.4) 1 Coumadin, n (%) 1 (2.2) 5 (13.5) 0.086 SSRI/SNRI, n (%) 7 (15.6) 9 (24.3) 0.404 ACEi 7 (15.6) 15 (40.5) 0.014 ARB 9 (20) 7 (18.9) 1 Hemoglobin, g/dL1 9.9 (1.7) 9.2 (2.3) 0.216 Platelets, 109/L1 225.4 (67.5) 208.6 (84.9) 0.202 BUN, mg/dL1 21.9 (13.1) 26.7 (22) 0.869 Creatinine, mg/dL1 1.3 (0.5) 1.9 (1.5) 0.197 Ferritin, ng/mL,1 128 (259) 39.6 (28.7) 0.966 Percent saturation, %1 14.8 (15.1) 13.7 (15.4) 0.76