title: Impact of BMI Variations on Survival in Elderly Hemodialysis Patients.
abstract: OBJECTIVE
  In elderly hemodialysis patients, protein-energy wasting is associated with poor outcome; however, the association between body mass index (BMI) changes over time, and survival has been seldom studied in this particularly frail population.
  
  
  METHODS
  This prospective study recruited 502 hemodialysis patients aged ≥75 years from the French cohort ARNOS and followed them from 2005 to 2009. BMI changes over time were modeled by individual linear regression models. Survival analyses used frailty Cox models.
  
  
  RESULTS
  The population average age was 80.9 years. Forty-one percent of the patients died during follow-up. A 1 kg/m(2) lower baseline BMI was associated with a 4% increase in the risk of death over the study period (hazard ratio [HR] 1.04, 95% confidence interval [1.01-1.08], P = .02). A 5% BMI loss per year was associated with a 52% increase in the risk of death (HR 1.52, 95% confidence interval [1.32-1.75], P < .001). In patients who lost weight (>5% BMI loss per year), the lower was the baseline BMI, the higher was the HR for death. There was a similar trend in the patients with stable weight (5% BMI loss-5% BMI gain per year). In patients who gained weight, the HR was unexpectedly higher than in those with stable weight.
  
  
  CONCLUSIONS
  In elderly hemodialysis patients, the impact of the BMI percent change on survival was stronger than that of the baseline BMI. Patients with stable weight had longer survivals than patients who lost or gained weight. Thus, in this population, BMI changes should be regularly assessed. Further studies should assess the safety of weight gain strategies.
authors.affiliation: Service de Biostatistique, Hospices Civils de Lyon, Lyon, France; Université de Lyon, Lyon, France; Université Lyon 1, Villeurbanne, France; CNRS, UMR5558, Equipe Biostatistique-Santé, Villeurbanne, France; Service de néphrologie-nutrition-dialyse, Centre Hospitalier Lyon Sud, Lyon, France. Electronic address: cedric.villain@chu-lyon.fr.
authors.forename: Cédric
authors.initials: C
authors.lastname: Villain
authors.affiliation: Service de Biostatistique, Hospices Civils de Lyon, Lyon, France; Université de Lyon, Lyon, France; Université Lyon 1, Villeurbanne, France; CNRS, UMR5558, Equipe Biostatistique-Santé, Villeurbanne, France.
authors.forename: René
authors.initials: R
authors.lastname: Ecochard
authors.affiliation: Service de néphrologie-nutrition-dialyse, Centre Hospitalier Lyon Sud, Lyon, France.
authors.forename: Leslie
authors.initials: L
authors.lastname: Genet
authors.affiliation: NephroCare Tassin-Charcot, Sainte-Foy-lès-Lyon, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Jean
authors.affiliation: Centre de Dialyse des Eaux Claires, AGDUC, Grenoble, France.
authors.forename: François
authors.initials: F
authors.lastname: Kuentz
authors.affiliation: Service de Néphrologie, Clinique Edouard Rist, Paris, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Lataillade
authors.affiliation: Service de Néphrologie et Hémodialyse, Centre Hospitalier d'Ardèche Nord, Annonay, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Legrand
authors.affiliation: Centre de Dialyse, Centre Hospitalier Général, AGDUC, Montélimar, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Moreau-Gaudry
authors.affiliation: Université de Lyon, Lyon, France; Université Lyon 1, Villeurbanne, France; Service de néphrologie-nutrition-dialyse, Centre Hospitalier Lyon Sud, Lyon, France; INSERM CarMeN, CENS, Université Lyon 1, Villeurbanne, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Fouque
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity; D016016:Proportional Hazards Models; D011446:Prospective Studies; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000401:mortality*; D012307:Risk Factors; D016019:Survival Analysis