title: Longitudinal association between serum leptin concentration and glomerular filtration rate in humans.
abstract: BACKGROUND
  Obesity is a risk factor for decline in glomerular filtration rate (GFR). One proposed mechanism leading to glomerulopathy is an increase in leptin levels. However, the association between leptin and GFR has never been demonstrated. The aim of this study is to verify whether higher levels of leptin are associated with longitudinal changes of estimated GFR (eGFR).
  
  
  RESULTS
  We selected 744 participants in the InCHIANTI study (416 women). The association between eGFR and leptin changes over a 6-years follow-up was assessed using random effect models including leptin as a time-varying covariate and adjusted for potential confounders. We also compared the proportion of patients with rapid decline of renal function across tertiles of change in serum leptin between baseline and 6-years follow-up. Mean baseline eGFR was 82.2 ml/min/1.73 m, 78.7 ml/min/1.73 m, and 75.4 ml/min/1.73 m in the first, second and third tertile of baseline serum leptin concentration, respectively. After adjustment for potential confounders, leptin concentration was inversely associated with changes of eGFR over time (β for log-leptin: -1.288, 95% CI: -2.079 - -0.497). Relative to baseline levels, the estimated change in eGFR for unit-increase in log-leptin was -1.9% (95% CI: -2.977 - -0.761). After stratification by sex, the results were confirmed in women only. In women we also found an association between increasing leptin concentration over time and rapid decline of renal function.
  
  
  CONCLUSIONS
  In women, serum leptin may contribute to eGFR decline independently from obesity and diabetes mellitus, although a cause-effect relationship cannot be established due to the observational nature of our study. A better characterization of adipokine profile of obese individuals may shed light on the accelerated renal function decline reported in a proportion of high-risk obese individuals.
authors.affiliation: Unit of Geriatrics, "Campus Biomedico" University, Rome, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Pedone
authors.affiliation: Department of Medicine, Division of Nephrology, University of Washington-Kidney Research Institute, Seattle, Washington, United States of America.
authors.forename: Baback
authors.initials: B
authors.lastname: Roshanravan
authors.affiliation: Unit of Geriatrics, "Campus Biomedico" University, Rome, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Scarlata
authors.affiliation: Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington, United States of America.
authors.forename: Kushang V
authors.initials: KV
authors.lastname: Patel
authors.affiliation: Longitudinal Study Section, Clinical research Branch, National Institute of Aging, Baltimore, Maryland, United States of America.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: Unit of Geriatrics, "Campus Biomedico" University, Rome, Italy; "S. Raffaele-Cittadella della Carità" Foundation, Taranto, Italy.
authors.forename: Raffaele Antonelli
authors.initials: RA
authors.lastname: Incalzi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003920:Diabetes Mellitus / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000503:physiopathology; D020738:Leptin / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000473:pathology; D012737:Sex Factors
chemical_list: D020738:Leptin