Obesity Abstracts

Post-bariatric-surgery hypoglycaemia (PBH) typically presents at least six months post-operatively, particularly in those who have undergone Roux-en-Y gastric bypass (RYGB). PBH is characterised by high postprandial insulin and glucagon-like peptide-1 secretion, leading to hypoglycaemia 1-3 hours after consumption of meals that are high in carbohydrate content. We present the case of a 47-year-old female, who underwent RYGB in 2009, without prior history of diabetes. Seven years after RYGB, she first noticed hypoglycaemic events while monitoring during pregnancy, which were mostly asymptomatic. Over the last few years, she has increasingly been experiencing autonomic symptoms 1-2 hours after high-carbohydrate meals, with capillary glucose levels dropping as low as 2.5mmol/l and symptoms improving after carbohydrate intake (Whipple’s triad). She did not report episodes of fasting hypoglycaemia, nor any other medical history other than vitiligo, and with alternative causes of hypoglycaemia excluded biochemically, a clinical diagnosis of PBH was made. She had a Freestyle Libre trial; during the fortnight she noted that with a strict low-carbohydrate diet, her glycaemic variability was reduced, and her symptoms and frequency of hypoglycaemia improved. She was not keen to take acarbose and has tried to manage PBH with dietary modification as per dietitian advice. She follows a low glycaemic-index carbohydrate intake diet (30 grams for meals, 15 grams for snacks) paired with vegetables, protein and healthy fats, taken every 3-4 hours, but she still experiences autonomic symptoms in daily life, affecting her quality of life. She reports that during the period using continuous-glucose-monitoring (CGM), she was more confident to modify her dietary choices to prevent post-prandial hypoglycaemia, and would be keen to continue using CGM, but the challenge remains that its use in PBH has not been approved by regulatory authorities in the UK. The literature demonstrates that CGM can help patients with PBH detect impending hypoglycaemia, allowing them to adopt dietary modification and early treatment to prevent and reduce post-prandial hypoglycaemia. Although currently not NHS-funded for PBH, CGM could be considered as a treatment option for PBH in clinical practice after dietetic intervention, and it may be particularly important for people experiencing disabling episodes of hypoglycaemia.