title: The German Chronic Kidney Disease (GCKD) study: design and methods.
abstract: BACKGROUND
  Chronic kidney disease (CKD) is increasingly recognized as a global health problem. The conditions leading to CKD, the health impact of CKD and the prognosis differ markedly between affected individuals. In particular, renal failure and cardiovascular mortality are competing risks for CKD patients. Opportunities for targeted intervention are very limited so far and require an improved understanding of the natural course of CKD, of the risk factors associated with various clinical end points and co-morbidities as well as of the underlying pathogenic mechanisms.
  
  
  METHODS
  The German Chronic Kidney Disease (GCKD) study is a prospective observational national cohort study. It aims to enrol a total of 5000 patients with CKD of various aetiologies, who are under nephrological care, and to follow them for up to 10 years. At the time of enrolment, male and female patients have an estimated glomerular filtration rate (eGFR) of 30-60 mL/min×1.73 m2 or overt proteinuria in the presence of an eGFR>60 mL/min×1.73 m2. Standardized collection of biomaterials, including DNA, serum, plasma and urine will allow identification and validation of biomarkers associated with CKD, CKD progression and related complications using hypothesis-driven and hypothesis-free approaches. Patient recruitment and follow-up is organized through a network of academic nephrology centres collaborating with practising nephrologists throughout the country.
  
  
  CONCLUSIONS
  The GCKD study will establish one of the largest cohorts to date of CKD patients not requiring renal replacement therapy. Similarities in its design with other observational CKD studies, including cohorts that have already been established in the USA and Japan, will allow comparative and joint analyses to identify important ethnic and geographic differences and to enhance opportunities for identification of relevant risk factors and markers.
authors.affiliation: Department of Nephrology and Hypertension, University of Erlangen-Nürnberg, Erlangen, Germany. kai-uwe.eckardt@uk-erlangen.de
authors.forename: Kai-Uwe
authors.initials: KU
authors.lastname: Eckardt
authors.forename: Barbara
authors.initials: B
authors.lastname: Bärthlein
authors.forename: Seema
authors.initials: S
authors.lastname: Baid-Agrawal
authors.forename: Andreas
authors.initials: A
authors.lastname: Beck
authors.forename: Martin
authors.initials: M
authors.lastname: Busch
authors.forename: Frank
authors.initials: F
authors.lastname: Eitner
authors.forename: Arif B
authors.initials: AB
authors.lastname: Ekici
authors.forename: Jürgen
authors.initials: J
authors.lastname: Floege
authors.forename: Olaf
authors.initials: O
authors.lastname: Gefeller
authors.forename: Hermann
authors.initials: H
authors.lastname: Haller
authors.forename: Robert
authors.initials: R
authors.lastname: Hilge
authors.forename: Karl F
authors.initials: KF
authors.lastname: Hilgers
authors.forename: Jan T
authors.initials: JT
authors.lastname: Kielstein
authors.forename: Vera
authors.initials: V
authors.lastname: Krane
authors.forename: Anna
authors.initials: A
authors.lastname: Köttgen
authors.forename: Florian
authors.initials: F
authors.lastname: Kronenberg
authors.forename: Peter
authors.initials: P
authors.lastname: Oefner
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Prokosch
authors.forename: André
authors.initials: A
authors.lastname: Reis
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmid
authors.forename: Elke
authors.initials: E
authors.lastname: Schaeffner
authors.forename: Ulla T
authors.initials: UT
authors.lastname: Schultheiss
authors.forename: Susanne A
authors.initials: SA
authors.lastname: Seuchter
authors.forename: Thomas
authors.initials: T
authors.lastname: Sitter
authors.forename: Claudia
authors.initials: C
authors.lastname: Sommerer
authors.forename: Gerd
authors.initials: G
authors.lastname: Walz
authors.forename: Christoph
authors.initials: C
authors.lastname: Wanner
authors.forename: Gunter
authors.initials: G
authors.lastname: Wolf
authors.forename: Martin
authors.initials: M
authors.lastname: Zeier
authors.forename: Stephanie
authors.initials: S
authors.lastname: Titze
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000209:etiology; D015897:Comorbidity; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005858:Germany; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011379:Prognosis; D011446:Prospective Studies; D011507:Proteinuria / Q000175:diagnosis* / Q000209:etiology; D012107:Research Design; D012307:Risk Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers