Hypotonic Low Esophageal Sphincter Is Not Predictive of Gastroesophageal Reflux Disease After Sleeve Gastrectomy.

BACKGROUND: Sleeve gastrectomy is the most commonly performed bariatric surgery these days but is associated with de novo reflux. OBJECTIVE: We aimed to study the influence of hypotonic lower esophageal sphincter (LES) on postoperative gastroesophageal reflux disease (GERD). METHODS: Patients with pre- and postoperative esophageal high-resolution manometry (HRM) and 24-h pH monitoring (pHM) were included retrospectively in our study. Preoperative hypotonic LES was defined by a mean residual pressure of the lower esophageal sphincter < 4 mmHg. Postoperative GERD was defined by a DeMeester's score > 14.72. We also evaluated postoperative manometric changes at the esophageal-gastric junction. RESULTS: Sixty-nine patients (54 females and 15 males) had pre- and postoperative HRM and pHM. The mean age was 45.9 ± 9.8 years. The mean body mass index (BMI) was 47.5 ± 7.5 kg/m2. Hypotonic LES concerned 21 patients (30.4%) before sleeve gastrectomy. The mean time between the two esophageal monitorings was 32.1 ± 24.1 months. The sensitivity, specificity, positive predictive value, and negative predictive value of hypotonic LES to predict GERD were 31, 70, 52, and 48% respectively. The LES minimal residual pressure was not statistically decreased after sleeve gastrectomy (p = 0.24). Only the wave speed, esophageal length, and LES length were significantly reduced after SG (p = 0.029, 3.8 × 10-7 and 0.00032). CONCLUSION: Hypotonic LES has a poor predictive value on postoperative GERD. The LES's length is significantly reduced after SG and this could be a factor explaining de novo reflux.

Roux-en-Y gastric bypass, but not sleeve gastrectomy, decreases plasma PCSK9 levels in morbidly obese patients.

AIM: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a master regulator of low-density lipoprotein cholesterol (LDL-C) metabolism, acting as an endogenous inhibitor of the LDL receptor. While it has been shown that bariatric surgery differentially affects plasma LDL-C levels, little is known of its effects on plasma PCSK9 concentrations. Therefore, the present study aimed to: (i) investigate the effect of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on plasma PCSK9 concentrations; and (ii) correlate baseline or postoperative plasma PCSK9 concentration variations with anthropometric and metabolic parameters. METHODS: Fasting plasma PCSK9 levels were measured by ELISA in morbidly obese patients before and 6 months after bariatric surgery. Patients were recruited from three prospective cohorts (in Nantes and Colombes in France, and Antwerp in Belgium). RESULTS: A total of 156 patients (34SG, 122RYGB) were included. Plasma PCSK9, LDL-C and non-high-density lipoprotein cholesterol (non-HDL-C) levels were significantly reduced after RYGB (-19.6%, -16.6% and -19.5%, respectively; P<0.0001), but not after SG. In all patients, postoperative PCSK9 change was positively correlated with fasting plasma glucose (FPG; r=0.22, P=0.007), HOMA-IR (r=0.24, P=0.005), total cholesterol (r=0.17, P=0.037) and non-HDL-C (r=0.17, P=0.038) variations, but not LDL-C. In contrast to what was observed for glucose parameters (FPG, HOMA-IR), correlation between PCSK9 and non-HDL-C changes after RYGB was independent of total weight loss. CONCLUSION: RYGB, but not SG, promotes a significant reduction in plasma PCSK9 levels, and such changes in circulating PCSK9 levels after RYGB appear to be more associated with glucose improvement than with lipid homoeostasis parameters.