title: Risk of Malnutrition, Trace Metal, and Vitamin Deficiency Post Roux-en-Y Gastric Bypass--a Prospective Study of 20 Patients with BMI < 35 kg/m².
abstract: BACKGROUND
  Due to its reliable effects on type 2 diabetes mellitus (T2DM) remission, Roux-en-Y gastric bypass (RYGB) has recently been investigated as a treatment option for nonseverely obese patients with T2DM (body mass index (BMI) <35 kg/m(2)). The purpose of this study was to investigate whether RGYB induces malnutrition of macro- and micronutrients within 24 months in these patients.
  
  
  METHODS
  A prospective cohort of 20 patients with longstanding, insulin-dependent T2DM and a BMI of 25-35 kg/m(2) were treated with RYGB. The patients were supplemented with over-the-counter, multivitamin, and micronutrient supplements. Serum concentrations of albumin, vitamins, and trace elements, hemoglobin, and bone density were measured preoperatively and over a 24-month period (DRKS00004605).
  
  
  RESULTS
  RYGB did not result in underweight or protein malnutrition. No new onset of deficiencies of water- or fat-soluble vitamins developed over the study period. However, serum selenium, zinc, and ferritin decreased significantly (selenium, 1.17 ± 0.13 to 0.89 ± 0.11 μmol/l, p = 0.018; zinc, 13.9 ± 0.5 to 10.8 ± 0.5 μmol/l, p = 0.012; ferritin, 171.7 ± 26.9 to 31.8 ± 11.2 μg/l, p = 0.018). Hemoglobin remained stable. Vitamin D (13.7 ± 1.8 to 19.1 ± 1.1 ng/ml, p = 0.017) and osteocalcin (15.3 ± 1.7 to 25.4 ± 2.7 ng/ml, p = 0.025) rose significantly, whereas the parathyroid hormone remained stable. Despite increased bone formation, bone density decreased (T score hip, 0.15 ± 0.25 to -0.71 ± 0.34, p = 0.005) resulting in a significant increase in osteopenia rates (18 to 50 %, p = 0.046).
  
  
  CONCLUSIONS
  This is the first prospective cohort to investigate malnutrition after RYGB in nonseverely obese patients. These patients are at risk of developing iron, selenium, and zinc deficiencies within 24 months, as well as osteopenia despite an increase in bone formation.
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Adrian T
authors.initials: AT
authors.lastname: Billeter
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Pascal
authors.initials: P
authors.lastname: Probst
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Fischer
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Jonas
authors.initials: J
authors.lastname: Senft
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Hannes G
authors.initials: HG
authors.lastname: Kenngott
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Thilo
authors.initials: T
authors.lastname: Schulte
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Clemens
authors.affiliation: Department of Internal Medicine I and Clinical Chemistry, University of Heidelberg, Heidelberg, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Zech
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
authors.forename: Markus W
authors.initials: MW
authors.lastname: Büchler
authors.affiliation: Department of Internal Medicine I and Clinical Chemistry, University of Heidelberg, Heidelberg, Germany.
authors.forename: Peter P
authors.initials: PP
authors.lastname: Nawroth
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany. beat.mueller@med.uni-heidelberg.de.
authors.forename: Beat P
authors.initials: BP
authors.lastname: Müller-Stich
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001361:Avitaminosis / Q000097:blood / Q000453:epidemiology*; D015992:Body Mass Index; D001851:Bone Diseases, Metabolic / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000601:surgery*; D005260:Female; D005293:Ferritins / Q000097:blood; D015390:Gastric Bypass / Q000009:adverse effects* / Q000706:statistics & numerical data; D006801:Humans; D000090463:Iron Deficiencies; D008286:Malabsorption Syndromes / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D008297:Male; D044342:Malnutrition / Q000097:blood / Q000453:epidemiology*; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000150:complications / Q000601:surgery*; D011183:Postoperative Complications / Q000097:blood / Q000453:epidemiology*; D012307:Risk Factors; D012643:Selenium / Q000172:deficiency; D014131:Trace Elements / Q000097:blood; D055815:Young Adult; D015032:Zinc / Q000097:blood / Q000172:deficiency
chemical_list: D014131:Trace Elements; D005293:Ferritins; D012643:Selenium; D015032:Zinc
keywords: Diabetes; Gastric bypass; Malabsorption; Malnutrition; Micronutrients; RYGB; Vitamin deficiency