title: Factors associated with serum leptin in patients with chronic kidney disease.
abstract: OBJECTIVE
  Serum leptin levels are elevated in patients with kidney failure. Data on the associations of serum leptin and on the relationship of leptin with both kidney function and inflammation, are limited in patients with reduced glomerular filtration rate (GFR). We evaluated the independent associations of serum leptin in patients with reduced GFR.
  
  
  METHODS
  Serum leptin and C-reactive protein (CRP) were measured in samples from 798 participants of the Modification of Diet in Renal Disease Study. Multivariable analysis was used to evaluate the independent effects of kidney function and CRP on leptin levels.
  
  
  RESULTS
  Median (interquartile range) of serum leptin was 9.1 ng/ml (14.0). Female gender, higher percent body fat, higher insulin levels, older age, lower GFR and higher CRP were associated with higher serum leptin levels and explained 51% of the variability in the logarithm of serum leptin levels. After adjusting for the other variables, a 10 ml/min/1.73 m2 lower GFR was associated with 6% higher mean serum leptin levels. Percent body fat and gender, explained 45% of the variability in serum leptin levels.
  
  
  CONCLUSIONS
  Level of kidney function and CRP are associated with serum leptin in patients with reduced GFR. However, there is a stronger association between serum leptin and indices of body fat and gender in patients in the earlier stages of chronic kidney disease. 50% of the variability remains unexplained in patients with reduced GFR.
authors.affiliation: Department of Medicine, Division of Clinical Care Research, Tufts-New England Medical Center, Boston, MA, USA.
authors.forename: V
authors.initials: V
authors.lastname: Menon
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: T
authors.initials: T
authors.lastname: Greene
authors.forename: G J
authors.initials: GJ
authors.lastname: Beck
authors.forename: J W
authors.initials: JW
authors.lastname: Kusek
authors.forename: S M
authors.initials: SM
authors.lastname: Marcovina
authors.forename: A S
authors.initials: AS
authors.lastname: Levey
authors.forename: M J
authors.initials: MJ
authors.lastname: Sarnak
mesh_terms: D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007328:Insulin / Q000097:blood; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000503:physiopathology; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012737:Sex Factors
chemical_list: D007328:Insulin; D020738:Leptin; D002097:C-Reactive Protein