Increased glycemic variability in pregnant women with Roux-en-Y gastric bypass compared with sleeve gastrectomy

Abstract

Introduction: Bariatric surgery is associated with adverse pregnancy outcomes such as reduced birth weight and premature birth. One possible mechanism for this is increased glycemic variability (GV) which occurs after bariatric surgery. The objective of this study was to compare the effect of Roux-en-Y gastric bypass (RYGB) versus vertical sleeve gastrectomy (SG) on GV during pregnancy and to investigate the relationships of GV, type of bariatric surgery and maternal and neonatal outcomes.

Research design and methods: Fourteen pregnant women after RYGB and 14 after SG were investigated with continuous glucose monitoring in their second or third trimester in this observational study carried out as part of routine clinical care.

Results: Pregnant women with RYGB had similar mean interstitial glucose values but significantly increased indices of GV and a lower %time in range 3.9-7.8 mmol/L (70-140 mg/dL), compared with SG.

Conclusions: Pregnant women who have undergone RYGB have greater GV during pregnancy compared with those who have undergone SG. Further research is needed to establish the relationship between GV and pregnancy outcomes to determine the preferred bariatric operation in women of reproductive age, and whether interventions to reduce GV might improve outcomes.

Keywords: bariatric surgery; pregnancy.

Figure 1

Relationship of surgical type (Roux-en-Y gastric bypass (RYGB); sleeve gastrectomy (SG)) to outcome measures. (A) Bar chart showing glucose variability (GV), expressed as %coefficient of variation (CV) of interstitial glucose, is higher with RYGB than SG; (B) bar chart showing percentage time spent in euglycemia (3.9–7.8 mmol/L, 70–140 mg/dL) is lower with RYGB than SG; (C) bar chart showing that gestational age at delivery is shorter with RYGB than with SG. For (A–C), means plotted for RYGB (filled bar) and SG (unfilled bar) and 95% CI indicated by error bars. Mean difference, 95% CI for difference, p value for unpaired two-tailed Student’s t-test is displayed on the top right-hand corner of the graph. (D) Scatter plot showing positive correlation of birth weight (y-axis) with gestational age at delivery (x-axis); (E) scatter plot showing negative correlation between %CV of interstitial glucose (y-axis) with gestational age at delivery (x-axis); (F) scatter plot showing negative correlation between percentage time spent in euglycemia (y-axis) with gestational age at delivery (x-axis). For (D–F), RYGB=filled circles, SG=unfilled squares. Line represents best-fit linear regression line and dashed lines the 95% CI of the regression line. Pearson’s correlation coefficient and p value indicated in the lower right-hand corner of the graph.