title: Incidence and risk factors for the development of anemia following gastric bypass surgery.
abstract: OBJECTIVE
  To evaluate the incidence and risk factors for the development of anemia after Roux-en-Y gastric bypass (RYGB).
  
  
  METHODS
  A retrospective analysis of patients undergoing RYGB from January 2003 to November 2007 was performed. All patients had a preoperative body mass index > 40 kg/m(2). A total of 206 patients were evaluated. All patients were given daily supplements of ferrous sulfate tablets for 2 wk following their operation. Hematological and metabolic indices were routinely evaluated following surgery. Patients were followed for a minimum of 86 wk.
  
  
  RESULTS
  There were 41 males and 165 females with an average age of 40.8 years. 21 patients (10.2%) developed post-operative anemia and 185 patients (89.8%) did not. Anemia was due to iron deficiency in all cases. The groups had similar demographics, surgical procedure and co-morbidities. Menstruation (P = 0.02) and peptic ulcer disease (P = 0.01) were risk factors for the development of post-operative anemia.
  
  
  CONCLUSIONS
  Iron deficiency anemia is frequent. RYGB surgery compounds occult blood loss. Increased ferrous sulfate supplementation may prevent iron depletion in populations at increased risk.
authors.affiliation: Department of Surgery, Beth Israel Medical Center, Albert Einstein College of Medicine, New York, NY 10003, United States.
authors.forename: Dimitrios V
authors.initials: DV
authors.lastname: Avgerinos
authors.forename: Omar H
authors.initials: OH
authors.lastname: Llaguna
authors.forename: Matthew
authors.initials: M
authors.lastname: Seigerman
authors.forename: Amanda J
authors.initials: AJ
authors.lastname: Lefkowitz
authors.forename: I Michael
authors.initials: IM
authors.lastname: Leitman
mesh_terms: D000328:Adult; D000740:Anemia / Q000175:diagnosis / Q000209:etiology*; D015992:Body Mass Index; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects* / Q000379:methods*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000601:surgery; D011183:Postoperative Complications; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
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