OR34-03 Defining Clinical Characteristics Of Patients With Severe Hypoglycemia After Roux-en-Y Gastric Bypass: How Do They Differ From Asymptomatic Patients?

Disclosure: A. Grover: None. A.L. Sheehan: None. C. Cummings: None. M. Farahmandsadr: None. H. Saeed: None. A.M. Puleio: None. D.C. Simonson: Stock Owner; Self; Phase V Technologies, GI Windows. M. Patti: Consulting Fee; Self; AstraZeneca, MBX-Biosciences, Hanmi Pharmaceutical. Other; Self; DSMB: Fractyl Health, Inc. Introduction: Post-bariatric hypoglycemia (PBH) is a severe, disabling complication of Roux-en-Y gastric bypass (RYGB). We aimed to identify clinical characteristics distinguishing patients with severe PBH vs. post-RYGB patients without symptomatic hypoglycemia (RYGB non-hypo) to help elucidate PBH pathophysiology and potential risk factors. Methods: Adults aged 18-70, without diabetes mellitus (DM), were recruited into 3 groups: (1) PBH with neuroglycopenia (n=33); (2) RYGB non-hypo (n=16); (3) non-surgical weight-matched controls (n=17). Detailed history of hypoglycemia, medical/surgical/family history, medications, Dumping Symptom Rating Scale (DSRS), and Rome IV diagnostic criteria for Irritable Bowel Syndrome (IBS) was completed. Differences between PBH and RYGB non-hypo were evaluated by unpaired t-tests and chi-square analysis as indicated. Results: PBH participants were 90% female, mean age 53±2 y, BMI 32±1 kg/m2, 39±2% body fat, with similar data for RYGB non-hypo (100% female, age 54±2 y, BMI 33±2 kg/m2, 40±2% fat), and controls (65% female, age 45±4 y, BMI 31±2 kg/m2, 35±3% fat). 90% of PBH reported level 3 hypoglycemia, with ER visits in 29% and motor vehicle accidents in 7%. Reduced awareness of hypoglycemia was reported by 80% of PBH, with hypoglycemia awareness at mean glucose of 57±2 mg/dL. 29% of PBH reported hypoglycemic symptoms occurring preoperatively, and 20% reported family history of hypoglycemia. The majority of PBH reported depression, change in driving habits, and adverse impact on employment. When compared with RYGB non-hypo, PBH participants had no difference in postoperative weight loss trajectories but had higher prevalence of revisional surgeries (p<0.05). PBH participants also had a higher score on DSRS (p<0.05) and higher prevalence of IBS (48 vs. 7% meeting Rome IV criteria, p<0.05). Higher rates of orthostatic hypotension, intestinal dysmotility, and vitamin B12 deficiency requiring treatment were reported by PBH (p<0.05 for all). Additionally, PBH participants reported greater gabapentin, PPI, and hormonal contraceptive use (p<0.05 for all); there were no differences in SSRI/SNRI use. Conclusion: PBH participants reported high rates of hypoglycemia unawareness, a likely contributor to hypoglycemia severity, recurrence, and adverse effects on safety and personal life. High rates of IBS, dumping symptoms, and orthostatic hypotension suggest possible disordered autonomic regulation in the pathophysiology of PBH. Self-reported preoperative symptoms and family history of hypoglycemia suggest possible differences in glucose metabolism prior to surgery in at-risk individuals. Preoperative assessment of these and other factors, together with longitudinal follow-up studies to determine incidence of PBH, will be required to identify risk factors for development of post-bariatric hypoglycemia. Presentation: Sunday, June 18, 2023