Hypoglycemia in everyday life after gastric bypass and duodenal switch

Abstract

Design: Gastric bypass (GBP) and duodenal switch (DS) in morbid obesity are accompanied by marked metabolic improvements, particularly in glucose control. In recent years, episodes of severe late postprandial hypoglycemia have been increasingly described in GBP patients; data in DS patients are scarce. We recruited three groups of subjects; 15 GBP, 15 DS, and 15 non-operated overweight controls to examine to what extent hypoglycemia occurs in daily life. Methods: Continuous glucose monitoring (CGM) was used during 3 days of normal activity. The glycemic variability was measured by mean amplitude of glycemic excursion and continuous overall net glycemic action. Fasting blood samples were drawn, and the patients kept a food and symptom log throughout the study. Results: The GBP group displayed highly variable CGM curves, and 2.9% of their time was spent in hypoglycemia (!3.3 mmol/l, or 60 mg/dl). The DS group had twice as much time in hypoglycemia (5.9%) and displayed CGM curves with little variation as well as lower HbA1c levels (29.3 vs 35.9 mmol/mol, P!0.05). Out of a total of 72 hypoglycemic episodes registered over the 3-day period, 70 (97%) occurred in the postprandial state and only about one-fifth of the hypoglycemic episodes in the GBP and DS groups were accompanied by symptoms. No hypoglycemias were seen in controls during the 3-day period. Conclusion: Both types of bariatric surgery induce marked, but different, changes in glucose balance accompanied by frequent, but mainly unnoticed, hypoglycemic episodes. The impact and mechanism of hypoglycemic unawareness after weight-reduction surgery deserves to be clarified.

Postprandial hypoglycaemia after Roux‐en‐Y gastric bypass and the effects of acarbose, sitagliptin, verapamil, liraglutide and pasireotide

“…Individuals with more severe postprandial hypoglycaemia exhibit higher postprandial insulin and GLP‐1 levels and, although the pathophysiological mechanisms are not completely understood, the exaggerated insulin and GLP‐1 responses are believed to be of great importance . Continuous glucose monitoring (CGM) has shown that hypoglycaemia is detectable in up to 75% of a population that has undergone RYGB, but is not symptomatic in all individuals . In individuals with symptoms, PBH is associated with reduced quality of life and weight regain, and PBH has been suggested to be related to the increased rate of accidental deaths seen after RYGB .…”

“…[1][2][3][4] Continuous glucose monitoring (CGM) has shown that hypoglycaemia is detectable in up to 75% of a population that has undergone RYGB, but is not symptomatic in all individuals. 5,6 In individuals with symptoms, PBH is associated with reduced quality of life and weight regain, and PBH has been suggested to be related to the increased rate of accidental deaths seen after RYGB. 7 Hypoglycaemic symptoms do not always correlate well with the severity of hypoglycaemia, and it is possible that rapid and large fluctuations in blood glucose levels account for some of the symptoms associated with PBH.…”

Hypoglycaemia after gastric bypass: mechanisms and treatment

“…Thus, Abrahamsson et al. used continuous glucose monitoring to show that patients with bypass or biliopancreatic diversion spend a significant amount of time with blood glucose levels <3.3 mmol/l (60 mg/dl) (2.9 and 5.9% of the time, respectively), while only 20% of this time is accompanied by symptoms. The most intriguing study is the one by Laurenius et al.…”

“…The hypothesis of hypoglycaemia 'unawareness' among patients remains valid, consistent with that which has been observed in type 1 diabetes [29]; that is, biological hypoglycaemia may be considered as pathological even in the absence of symptoms recognized by the patients. Thus, Abrahamsson et al [25] used continuous glucose monitoring to show that patients with bypass or biliopancreatic diversion spend a significant amount of time with blood glucose levels <3.3 mmol/l (60 mg/dl) (2.9 and 5.9% of the time, respectively), while only 20% of this time is accompanied by symptoms. The most intriguing study is the one by Laurenius et al [26], comparing patients with a very severe clinical presentation with asymptomatic patients, which found no difference in glycaemia, plasma insulin or glucagon profiles between the patient groups.…”

Impact of Carbohydrate Content and Glycemic Load on Postprandial Glucose After Roux-en-Y Gastric Bypass

“…In nondiabetic patients, within the 2 weeks following a RYGB, the quantity of carbohydrates (25 or 50 g in solution) and the glycemic index of the meal (mixed meal test with 37.5 g of glucose) do not impact the maximum plasma glucose [20]. Furthermore, Abrahamson et al illustrated that low glucose concentrations observed in real life were not always found under laboratory conditions (OGTT or mixed meal test) [21].…”