title: Prevalence and complications of chronic kidney disease in a representative elderly population in Iceland.
abstract: BACKGROUND
  Chronic kidney disease (CKD) is common in the elderly, but data are limited on the distribution of glomerular filtration rate (GFR) and albuminuria and the prevalence of CKD and related complications in this population.
  
  
  METHODS
  A cross-sectional study of 3173 older Icelandic adults [42% men; mean (standard deviation, SD) age of 80 (5) years] was performed to examine the distribution of estimated glomerular filtration rate (eGFR) from creatinine and cystatin C, the albumin-to-creatinine ratio (ACR), and CKD-related metabolic complications (hyperparathyroidism, anemia, hypoalbuminemia, increased anion gap, acidosis, hyperphosphatemia and hyperkalemia).
  
  
  RESULTS
  There was substantial variability in eGFR [mean (SD) 64 (18) mL/min/1.73 m(2)] and ACR [median (interquartile range) 8 (5, 17) mg/g]. The prevalence (95% confidence interval) of reduced eGFR (<60 mL/min/1.73 m(2)), albuminuria (ACR >30 mg/g) and CKD (either reduced eGFR or albuminuria) was 40% (38-41), 14% (12-15) and 45% (43-47), respectively. The prevalence of complications was higher among those with versus without CKD: hyperparathyroidism (38 versus 15%), anemia (26 versus 14%), hypoalbuminemia (19 versus 13%), increased anion gap (9 versus 5%), acidosis (5 versus 1%); (P ≤ 0.02 for all), except hyperphosphatemia (1 versus 1%) and hyperkalemia (0% overall).
  
  
  CONCLUSIONS
  The burden of CKD and CKD-related complications is high among community dwelling elderly Icelandic adults. The wide range of eGFR and ACR suggests heterogeneity in processes leading to CKD and that factors beyond aging contribute to the development of CKD in the elderly.
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA, USA.
authors.forename: Aghogho
authors.initials: A
authors.lastname: Okparavero
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA, USA.
authors.forename: Meredith C
authors.initials: MC
authors.lastname: Foster
authors.affiliation: The Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA, USA Tufts Clinical and Translational Science Institute, Tufts University, Boston, MA, USA.
authors.forename: Hocine
authors.initials: H
authors.lastname: Tighiouart
authors.affiliation: Icelandic Heart Association, Kopavogur, Iceland University of Iceland, Reykjavik, Iceland.
authors.forename: Vilmundur
authors.initials: V
authors.lastname: Gudnason
authors.affiliation: Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland.
authors.forename: Olafur
authors.initials: O
authors.lastname: Indridason
authors.affiliation: University of Iceland, Reykjavik, Iceland Landspitali-The National University Hospital of Iceland, Reykjavik, Iceland.
authors.forename: Hrefna
authors.initials: H
authors.lastname: Gudmundsdottir
authors.affiliation: Icelandic Heart Association, Kopavogur, Iceland.
authors.forename: Gudny
authors.initials: G
authors.lastname: Eiriksdottir
authors.affiliation: Icelandic Heart Association, Kopavogur, Iceland.
authors.forename: Elias F
authors.initials: EF
authors.lastname: Gudmundsson
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA, USA.
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Inker
authors.affiliation: Division of Nephrology, Tufts Medical Center, Boston, MA, USA.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Levey
mesh_terms: D000367:Age Factors; D000369:Aged, 80 and over; D000740:Anemia / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000209:etiology; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007055:Iceland / Q000453:epidemiology; D008297:Male; D008659:Metabolic Diseases / Q000453:epidemiology* / Q000209:etiology; D015995:Prevalence; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D012307:Risk Factors
keywords: albuminuria; chronic kidney disease; complications; elderly; prevalence