title: Assessment of kidney function in the elderly: a population-based study.
abstract: BACKGROUND
  Chronic kidney disease (CKD) affects all age groups, and its prevalence has increased during recent years. CKD is divided into six stages, according to the renal function of patients: 1. Normal renal function without kidney damage; 2. Kidney damage with normal renal function; 3. Mild renal insufficiency; 4. Moderate renal insufficiency or lab tests failure; 5. Severe renal insufficiency or clinical failure; 6. End stage of chronic renal failure.
  
  
  OBJECTIVE
  This study was intended to assess renal function in elderly patients and identifying the presence of factors associated with those changes.
  
  
  METHODS
  A cross-sectional population-based study was performed. Elderly patients were surveyed between September 2010 and May 2011. Kidney function was assessed by determining of serum creatinine, and estimation of the glomerular filtration rate by the CKD-EPI equation.
  
  
  RESULTS
  In all, 822 elderly were surveyed; 61.6% were women; 92.2% were Caucasian; and most (61.0%) were aged between 60 and 69 years. With regard to the glomerular filtration rate, 26.2% had a normal rate; 60.2% showed a slight decrease; 13.0% a moderate decrease; 0.5% severe kidney function decline; and 0.1% extreme fall. Increasing age was associated with kidney damage by decreased glomerular filtration rate (p < 0.001). In addition, obesity, hypertension and smoking were factors independently associated with reduced glomerular filtration rates.
  
  
  CONCLUSIONS
  This study found that the great majority of the surveyed elderly had some mild kidney damage, and 13.6% showed moderate to severe dysfunction.
authors.affiliation: Universidade do Sul de Santa Catarina.
authors.forename: Marina Constante
authors.initials: MC
authors.lastname: Dutra
authors.affiliation: Universidade do Sul de Santa Catarina.
authors.forename: Estevão José Muller
authors.initials: EJ
authors.lastname: Uliano
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina.
authors.forename: Danúbia Felippe Grassi de Paula
authors.initials: DF
authors.lastname: Machado
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Martins
authors.affiliation: Universidade do Sul de Santa Catarina.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Schuelter-Trevisol
authors.affiliation: Universidade do Sul de Santa Catarina.
authors.forename: Daisson José
authors.initials: DJ
authors.lastname: Trevisol
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007668:Kidney / Q000502:physiology*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000175:diagnosis / Q000503:physiopathology