title: Impact of Preoperative Serum Vitamin D Level on Postoperative Complications and Excess Weight Loss After Gastric Bypass.
abstract: The aim of this study was to determine the impact of hypovitaminosis D on Gastric Bypass outcomes.
  
  
  
  We retrospectively reviewed all patients who underwent primary intention Gastric Bypass in our center between January 2012 and December 2013. Postoperative complications, 1 and 2-year excess weight loss were compared between patients with and without hypovitaminosis D.
  
  
  
  Among 258 patients who met inclusion criteria, 56 (21.7%) presented with vitamin D deficiency. Mean age was 41.73 ± 12.95 years. Mean BMI was 40.90 kg/m2(34-58 kg/m2). No statistically significant difference in postoperative complication rate was found between patients with and without hypovitaminosis D. Mean 1-year excess weight loss was 75.24%. In patients with vitamin D deficiency mean 1-year excess weight loss was 71.90 versus 76.15% in patients with optimal serum vitamin D level (p = 0.17). No significant difference was found after a 2-year follow-up. In patients presenting with vitamin D insufficiency, 1-year excess weight loss was 75.64 versus 79.34% in patients with optimal serum vitamin D level (p = 0.53). After a 2-year follow-up, there was a significant difference between patients presenting with and without vitamin D insufficiency (79.45 versus 91.71%; p = 0.01) and between patients presenting with and without hypovitaminosis D (80.50 versus 91.71%; p = 0.01).
  
  
  
  In our study, hypovitaminosis D seemed to have a negative impact on long term excess weight loss, but not on short-term outcome or postoperative complications. The role of systematic supplementation before bariatric surgery has to be explored in prospective studies.
authors.affiliation: Service de Chirurgie Digestive et Transplantation Hépatique, Hôpital Archet 2, Centre Hospitalo Universitaire, Université de Nice Sophia Antipolis, Nice, France. schaaf.c@chu-nice.fr.
authors.forename: Caroline
authors.initials: C
authors.lastname: Schaaf
authors.affiliation: Service de Chirurgie Digestive et Transplantation Hépatique, Hôpital Archet 2, Centre Hospitalo Universitaire, Université de Nice Sophia Antipolis, Nice, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Gugenheim
mesh_terms: D000328:Adult; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000150:complications / Q000601:surgery*; D011183:Postoperative Complications; D057234:Preoperative Period; D011446:Prospective Studies; D012189:Retrospective Studies; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications; D015431:Weight Loss
chemical_list: D014807:Vitamin D
keywords: Excess weight loss; Gastric bypass; Hypovitaminosis D; Postoperative complications; Vitamin D