The incidence and risk factors associated with developing symptoms of hypoglycemia after bariatric surgery

Background: Hypoglycemia after bariatric surgery is an increasingly recognized metabolic complication associated with exaggerated secretion of insulin and gut hormones. Objective: We sought to determine the incidence of hypoglycemic symptoms (hypo-sx) after bariatric surgery and characteristics of those affected compared with those unaffected. Setting: University hospital. Methods: We collected retrospective survey data from the patients who underwent bariatric surgery at a single center. Based on number and severity of postprandial hypo-sx in Edinburgh hypoglycemia questionnaire postoperatively, patients without preoperative hypo-sx were grouped into high versus low suspicion for hypoglycemia. We used multivariable logistic regression to examine potential baseline and operative risk factors for the development of hypo-sx after surgery. Results: Among the 1119 patients who had undergone bariatric surgery who received the questionnaire, 464 (40.6%) responded. Among the 341 respondents without preexisting hypo-sx, 29% (n = 99) had new-onset hypo-sx, and most were severe cases (n = 92) with neuroglycopenic symptoms. Compared with the low suspicion group, the high suspicion group consisted of more female patients, younger patients, patients without diabetes, and those who underwent Roux-en-Y gastric bypass with a longer time since surgery and more weight loss. In multivariate analysis, factors independently associated with incidence of hypo-sx after bariatric surgery were female sex (P =.003), Roux-en-Y gastric bypass (P =.001), and absence of preexisting diabetes (P =.011). Conclusions: New onset postprandial hypoglycemic symptoms after bariatric surgery are common, affecting up to a third of those who underwent bariatric surgery. Many affected individuals reported neuroglycopenic symptoms and were more likely to be female and nondiabetic and to have undergone Roux-en-Y gastric bypass.