title: Sarcopenia in chronic kidney disease on conservative therapy: prevalence and association with mortality.
abstract: BACKGROUND
  In chronic kidney disease (CKD), multiple metabolic and nutritional abnormalities contribute to the impairment of skeletal muscle mass and function thus predisposing patients to the condition of sarcopenia. Herein, we investigated the prevalence and mortality predictive power of sarcopenia, defined by three different methods, in non-dialysis-dependent (NDD) CKD patients.
  
  
  METHODS
  We evaluated 287 NDD-CKD patients in stages 3-5 [59.9 ± 10.5 years; 62% men; 49% diabetics; glomerular filtration rate (GFR) 25.0 ± 15.8 mL/min/1.73 m(2)]. Sarcopenia was defined as reduced muscle function assessed by handgrip strength (HGS <30th percentile of a population-based reference adjusted for sex and age) plus diminished muscle mass assessed by three different methods: (i) midarm muscle circumference (MAMC) <90% of reference value (A), (ii) muscle wasting by subjective global assessment (B) and (iii) reduced skeletal muscle mass index (<10.76 kg/m² men; <6.76 kg/m² women) estimated by bioelectrical impedance analysis (BIA) (C). Patients were followed for up to 40 months for all-cause mortality, and there was no loss of follow-up.
  
  
  RESULTS
  The prevalence of sarcopenia was 9.8% (A), 9.4% (B) and 5.9% (C). The kappa agreement between the methods were 0.69 (A versus B), 0.49 (A versus C) and 0.46 (B versus C). During follow-up, 51 patients (18%) died, and the frequency of sarcopenia was significantly higher among non-survivors. In crude Cox analysis, sarcopenia diagnosed by the three methods was associated with a higher hazard for mortality; however, only sarcopenia diagnosed by method C remained as a predictor of mortality after multivariate adjustment.
  
  
  CONCLUSIONS
  The prevalence of sarcopenia in CKD patients on conservative therapy varies according to the method applied. Sarcopenia defined as reduced handgrip strength and low skeletal muscle mass index estimated by BIA was an independent predictor of mortality in these patients.
authors.affiliation: Nutrition Program and Nephrology Division, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Raíssa A
authors.initials: RA
authors.lastname: Pereira
authors.affiliation: Department of Hypertension and Nephrology, Dante Pazzanese Institute of Cardiology, São Paulo, Brazil.
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Cordeiro
authors.affiliation: Nutrition Institute, Rio de Janeiro State University, Rio de Janeiro, Brazil.
authors.forename: Carla M
authors.initials: CM
authors.lastname: Avesani
authors.affiliation: Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Carrero
authors.affiliation: Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Bengt
authors.initials: B
authors.lastname: Lindholm
authors.affiliation: Department of Hypertension and Nephrology, Dante Pazzanese Institute of Cardiology, São Paulo, Brazil.
authors.forename: Fernanda C
authors.initials: FC
authors.lastname: Amparo
authors.affiliation: Department of Hypertension and Nephrology, Dante Pazzanese Institute of Cardiology, São Paulo, Brazil.
authors.forename: Celso
authors.initials: C
authors.lastname: Amodeo
authors.affiliation: Nutrition Program and Nephrology Division, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Lilian
authors.initials: L
authors.lastname: Cuppari
authors.affiliation: Nutrition Program and Nephrology Division, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Kamimura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005260:Female; D005919:Glomerular Filtration Rate; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009133:Muscular Atrophy / Q000503:physiopathology*; D015995:Prevalence; D011379:Prognosis; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000401:mortality / Q000628:therapy*; D055948:Sarcopenia / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality*; D015996:Survival Rate; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult
keywords: chronic kidney disease; handgrip strength; mortality; muscle mass; sarcopenia