title: Validation of chronic kidney disease risk categorization system in Chinese patients with kidney disease: A cohort study.
abstract: OBJECTIVE
  To validate the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines risk stratification system based on the combination of estimated glomerular filtration rate (eGFR) and proteinuria.
  
  
  METHODS
  This was a cohort study. A total of 1219 study population were recruited. Estimated GFR and proteinuria measured by using 24 h urine protein excretion rate (PER) were predictors. Adverse outcomes included all-cause mortality (ACM) and end-stage renal disease (ESRD). Follow-up was done by regular visit, telephone interview and electronic medical records.
  
  
  RESULTS
  Over a median follow-up of 4.6 years, 153 (12.6%) and 43 (3.5%) patients experienced ESRD and ACM, respectively. On multivariable analysis, the adjusted hazard ratio for ESRD and ACM (compared with patients with eGFR > 60 mL/min per 1.7  m²) was of 29.8 and 3.6 for those with eGFR of 15-29 mL/min per 1.73 m², respectively. The adjusted hazard ratio for ESRD and ACM (compared with patients with PER < 150 mg/24h) was of 15.9 and 3.9 for those with PER > 500 mg/24h. Higher KDIGO guidelines risk categories (indicating lower eGFR or higher proteinuria) were associated with a graded increase in the risk for the ESRD (P < 0.001) and ACM (P < 0.001). Reclassification of KDIGO guidelines risk categories yielded net reclassification improvements for those with ESRD or ACM event (NRIevents ) of 33.3% or 30.2%.
  
  
  CONCLUSIONS
  Lower eGFR and higher proteinuria are risk factors for ESRD and ACM in Chinese patients. The KDIGO guidelines risk categorization system assigned patients who went on to have the event to more appropriate CKD risk categories.
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Qingyan
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Division of Nephrology and Institute of Nephrology, Peking University First Hospital, Beijing, China.|Key Laboratory of Renal Disease, Ministry of Health of China, Beijing, China.|Key Laboratory of Chronic Kidney Disease Prevention and Treatment (Peking University), Ministry of Education, Beijing, China.
authors.forename: Jicheng
authors.initials: J
authors.lastname: Lv
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Jiao
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Yinan
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.
authors.forename: Guobin
authors.initials: G
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People; D002423:Cause of Death; D002681:China / Q000453:epidemiology; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000503:physiopathology*; D007676:Kidney Failure, Chronic / Q000208:ethnology / Q000401:mortality / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011507:Proteinuria / Q000145:classification / Q000175:diagnosis / Q000208:ethnology* / Q000401:mortality / Q000503:physiopathology; D051436:Renal Insufficiency, Chronic / Q000145:classification / Q000175:diagnosis / Q000208:ethnology* / Q000401:mortality / Q000503:physiopathology; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016482:Urinalysis
keywords: chronic kidney disease; glomerular filtration rate; prognosis; proteinuria