title: Trends in mortality in bariatric surgery: a systematic review and meta-analysis.
abstract: BACKGROUND
  This is the first systematic review and meta-analysis of published mortality data after bariatric surgery.
  
  
  METHODS
  The review includes all papers published in English from January 1, 1990 to April 30, 2006, identified through electronic searches in MEDLINE, Current Contents, and the Cochrane Library, supplemented by manual reference checks. All accepted studies were assigned a level of evidence (Centre for Evidence-Based Medicine, Oxford, UK), and randomized controlled trials were rated for quality using the Jadad scoring method. Random effects meta-analyses were performed. Mortality was analyzed at either <or=30 days or 30 days to 2 years.
  
  
  RESULTS
  The data set includes 361 studies with 478 treatment arms and 85,048 patients. At baseline, the mean age was 40.0 years, body mass index was 47.4 kg/m2, 85% were female, and 11.5% had previous bariatric procedures. Meta-analysis of total mortality at <or=30 days was 0.28% (95% confidence interval [CI], 0.22-0.34) in 475 treatment arms (n = 84,931); total mortality at >30 days to 2 years was 0.35% (95% CI, 0.12-0.58) in 140 treatment arms (n = 19,928). Mortality at <or=30 day for all restrictive procedures was 0.30% (95% CI, 0.15-0.46) for open and 0.07% (95% CI, 0.02-0.12) for laparoscopic procedures; restrictive/malabsorptive (gastric bypass) was 0.41% (95% CI, 0.24-0.58] for open and 0.16% (95% CI, 0.09-0.23) for laparoscopic; and malabsorptive was 0.76% (95% CI, 0.29-1.23) for open and 1.11% (95% CI, 0.00-2.70) for laparoscopic. Subgroup analyses of <or=30-day mortality show a male:female ratio of 4.74:0.13, with 1.25% (95% CI, 0.56-1.94) incidence in the superobese and 0.34% (95% CI, 0.00-1.29) in the elderly (>or=65 years).
  
  
  CONCLUSIONS
  The early and late mortality rates after bariatric surgery are low and can be subjected to risk stratification for comparative analyses and prospective risk assessments.
authors.affiliation: University of Minnesota, Minneapolis, MN 55455, USA. buchw001@umn.edu
authors.forename: Henry
authors.initials: H
authors.lastname: Buchwald
authors.forename: Rhonda
authors.initials: R
authors.lastname: Estok
authors.forename: Kyle
authors.initials: K
authors.lastname: Fahrbach
authors.forename: Deirdre
authors.initials: D
authors.lastname: Banel
authors.forename: Isabella
authors.initials: I
authors.lastname: Sledge
mesh_terms: D050110:Bariatric Surgery / Q000401:mortality*; D015897:Comorbidity; D006801:Humans; D009767:Obesity, Morbid / Q000401:mortality* / Q000601:surgery*; D018570:Risk Assessment