1218 the Relationship Between Gastric Food Residue and the Rate of Gastric Emptying

INTRODUCTION: Gastric food residue (GFR) identified during gastrointestinal (GI) endoscopy is assumed to reflect delayed gastric emptying (GE [i.e., gastroparesis]). The aims of this study aims were to determine i) the prevalence of GFR during upper GI endoscopy (EGD) and, ii) the relationship between GFR and GE, structural abnormalities and diseases associated with gastroparesis. METHODS: Electronic health records were used to identify patients who had undergone both EGD and gastric emptying scintigraphy (GES) between October 2013 and September 2018. The test meal included radiolabeled scrambled eggs (320 kcal, 30% fat). Data were collected via the Advanced Cohort Explorer (ACE) application available at Mayo Clinic. The presence of GFR, structural or physiological factors associated with delayed GE was determined. Descriptive and comparative analyses were performed. RESULTS: In the 5 year period, the prevalence of GFR during upper GI endoscopy was 3.2% per patient and 2.5% per procedure (37% or patients had undergone >1 procedure). Of 3169 patients who underwent both EGD and GES available for review, 230 (7.3%) had GFR. Type 1 diabetes mellitus (DM, 22% vs 7%, P < 0.001) and type 2 DM (13% vs 7%, P < 0.05), but not systemic sclerosis (P = 0.1), were associated with GFR. Relative to patients with no GFR, patients with GFR had reduced GE at 2 and 4 hours (35% vs 46%, P < 0.001 and 67% vs 81%, P < 0.001 respectively) and were more likely to have structural abnormalities in the stomach or small bowel (e.g., surgery/stenosis, 14% GFR vs. 5%, P < 0.001) or have predisposing medical conditions (e.g. DM, systemic sclerosis, 20% GFR vs. 8%, P < 0.001). GE rates for patients with these conditions are shown in Table 1. Among those with no structural abnormalities or medical conditions associated with delayed GE, GE at 2 hours and 4 hours was significantly reduced in patient with GFR compared to those without GFR (37% vs 46%, and 69% vs 81%, both P < 0.001 respectively). The proportion of patients with delayed GE at 2 and 4 hours was greater in patients with GFR than without (42% vs 22% and 35% vs. 54%, both P < 0.001). CONCLUSION: GFR is encountered in 3% of all EGDs. In a cohort undergoing endoscopy and GES, ∼20% of patients with type 1 DM demonstrated GFR. The presence of GFR during endoscopy is associated with retarded GE. However, almost 50% of patients with GFR will have normal GE; therefore the presence of GFR at EGD does not accurately reflect gastric retention of digestible solids.