Rate of post-bariatric hypoglycemia using continuous glucose monitoring: A meta-analysis of literature studies

Nutr Metab Cardiovasc Dis. 2022 Jan;32(1):32-39. doi: 10.1016/j.numecd.2021.08.047. Epub 2021 Sep 25.


Aims: Hypoglycemia is a serious complication of bariatric surgery. The aim of the present meta-analysis was to evaluate the rate and the timing of post-bariatric hypoglycemia (PBH) with different bariatric procedures using reliable data from continuous glucose monitoring (CGM).

Data synthesis: Studies were systematically searched in the Web of Science, Scopus and PubMed databases according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The prevalence of PBH was expressed as weighted mean prevalence (WMP) with pertinent 95% confidence intervals (95%CI). A total of 8 studies (16 datasets) enrolling 280 bariatric subjects were identified. The total WMP of PBH was 54.3% (95%CI: 44.5%-63.8%) while the WMP of nocturnal PBH was 16.4% (95%CI: 7.0%-34%). We found a comparable rate of PBH after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) (OR 1.62, 95%CI: 0.71-3.7; P = 0.248); likewise, the percent time spent in hypoglycemia was similar with the two procedures (mean difference 5.3%, 95%CI: -1.4%-12.0%; P = 0.122); however, RYGB was characterized by a higher glycemic variability than SG. Regression models showed that the time elapsed from surgical intervention was positively associated with a higher rate of both total PBH (Z-value: 3.32, P < 0.001) and nocturnal PBH (Z-value: 2.15, P = 0.013).

Conclusions: PBH, both post-prandial and nocturnal, is more prevalent than currently believed. The rate of PBH increases at increasing time from surgery and is comparable after RYGB and SG with a higher glucose variability after RYGB.

Keywords: Bariatric surgery; Continuous glucose monitoring; Hypoglycemia; Obesity.

Publication types

  • Meta-Analysis

MeSH terms

  • Blood Glucose
  • Blood Glucose Self-Monitoring / adverse effects
  • Gastrectomy / adverse effects
  • Gastric Bypass* / adverse effects
  • Humans
  • Hypoglycemia* / diagnosis
  • Hypoglycemia* / etiology
  • Obesity, Morbid* / complications
  • Obesity, Morbid* / diagnosis
  • Obesity, Morbid* / surgery


  • Blood Glucose