title: Association of frailty with endothelial dysfunction and its possible impact on negative outcomes in Brazilian predialysis patients with chronic kidney disease.
abstract: BACKGROUND
  Frailty is a state of physiological vulnerability common in the elderly. It is more predominant in patients with Chronic Kidney Disease in comparison to healthy subjects, which can also be diagnosed in non-elderly individuals and be associated with innumerous causes such as muscle strength, body composition and inflammation. The association between frailty and endothelial function, as well as the association between frailty and the combined outcome of mortality multiple cause and start of renal replace therapy were assessed.
  
  
  METHODS
  In the initial analysis, sixty-one predialysis patients with Chronic Kidney Disease stages were evaluated and included in this study. Due to patient drop-out during follow-up, fifty-seven patients were subsequently re-evaluated 12 months later. The diagnosis of frailty was based on the Johansen et al. (J Am Soc Nephrol 18(11):2960-67, 2007) criteria. The groups were divided into Non-frail and Frail. Sociodemographic, inflammatory markers (IL-6, TNF-?, CRP-us), endothelial dysfunction (flow-mediated vasodilatation - FMD), body composition (DXA) and the 25-hidroxi-vitamin D parameters were analyzed.
  
  
  RESULTS
  The average age of the patients used in the study was 64.9 ± 10.3 years old. The predominance of frailty was 42.6%, of which 46% were non-elderly. After some adjustments, frailty was associated with gender (OR = 11.32; IC 95% = 2.30 to 55.67), advanced age (OR = 4.07; IC 95% = 1.02 to 16.20), obesity (OR = 6.63; IC 95% = 0.82 to 11.44) and endothelial dysfunction (OR = 3.86; IC 95% = 1.00 to 14.88). The ratio of the incidence of frail subjects to the variable outcome was 2.5 (CI 95%, 1.04 to 6.50).
  
  
  CONCLUSIONS
  Although an observational study does not allow one to determine the casual relation between frailty and endothelial dysfunction, we conclude that frailty was predominant in our sample of Brazilian patients with chronic kidney disease on predialysis, even in elderly individuals. This was linked to either worse endothelial function or mortality.
authors.affiliation: IMEPEN Foundation, Federal University of Juiz de Fora, Juiz de Fora, Brazil. hnmansur@gmail.com.|Academic Centre of Vitoria, Federal University of Pernambuco, Vitória de Santo Antão, Pernambuco, Brazil. hnmansur@gmail.com.
authors.forename: Henrique Novais
authors.initials: HN
authors.lastname: Mansur
authors.affiliation: IMEPEN Foundation, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
authors.forename: Júlio César Moraes
authors.initials: JC
authors.lastname: Lovisi
authors.affiliation: IMEPEN Foundation, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
authors.forename: Fernando Antonio Basile
authors.initials: FA
authors.lastname: Colugnati
authors.affiliation: IMEPEN Foundation, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
authors.forename: Nadia Rezende Barbosa
authors.initials: NR
authors.lastname: Raposo
authors.affiliation: IMEPEN Foundation, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
authors.forename: Natália Maria da Silva
authors.initials: NM
authors.lastname: Fernandes
authors.affiliation: Federal University of Juiz de Fora, José Lourenço Kelmer Street, 1300, Juiz de Fora, Minas Gerais, Brazil. marcusbastos7@gmail.com.
authors.forename: Marcus Gomes
authors.initials: MG
authors.lastname: Bastos
mesh_terms: D000368:Aged; D001938:Brazil; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D016330:Frail Elderly; D006801:Humans; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D016896:Treatment Outcome