title: Predicting 5-Year Risk of RRT in Stage 3 or 4 CKD: Development and External Validation.
abstract: Only a minority of patients with CKD progress to renal failure. Despite the potential benefits of risk stratification in the CKD population, risk prediction models are not routinely used. Our objective was to develop and externally validate a clinically useful and pragmatic prediction model for the 5-year risk of progression to RRT in stage 3 or 4 CKD.
  
  
  
  We used a retrospective cohort design. The development cohort consisted of 22,460 Kaiser Permanente Northwest members with stage 3 or 4 CKD (baseline 2002-2008). The validation cohort consisted of 16,553 Kaiser Permanente Colorado members with stage 3-4 CKD (baseline 2006-2008). The final model included eight predictors: age, sex, eGFR, hemoglobin, proteinuria/albuminuria, systolic BP, antihypertensive medication use, and diabetes and its complications.
  
  
  
  In the Northwest and Colorado cohorts, there were 737 and 360 events, and observed 5-year Kaplan-Meier risks of 4.72% (95% confidence interval [95% CI], 4.38 to 5.06) and 2.57% (95% CI, 2.30 to 2.83), respectively. Our prediction model performed extremely well in the development cohort, with a c-statistic of 0.96, an R2of 79.7%, and good calibration. We had similarly good performance in the external validation cohort, with a c-statistic of 0.95, R2of 81.2%, and good calibration. In the external validation cohort, the observed risk was slightly lower than the predicted risk in the highest-risk quintile. Using the top quintile of predicted risk as a cutpoint gave a sensitivity of 92.2%.
  
  
  
  We developed a pragmatic prediction model and risk score for predicting the 5-year RRT risk in stage 3 and 4 CKD. This model uses variables that are typically available in routine primary care settings, and can be used to help guide important decisions such as timing of referral to nephrology and fistula placement.
authors.affiliation: Institute for Health Research and.|Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado.
authors.forename: Emily B
authors.initials: EB
authors.lastname: Schroeder
authors.affiliation: Center for Health Research and.
authors.forename: Xiuhai
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Nephrology, Kaiser Permanente Northwest, Portland, Oregon; and.
authors.forename: Micah L
authors.initials: ML
authors.lastname: Thorp
authors.affiliation: Department of Nephrology, Kaiser Permanente Colorado, Denver, Colorado.
authors.forename: Brent M
authors.initials: BM
authors.lastname: Arnold
authors.affiliation: Institute for Health Research and.
authors.forename: David C
authors.initials: DC
authors.lastname: Tabano
authors.affiliation: Center for Health Research and.
authors.forename: Amanda F
authors.initials: AF
authors.lastname: Petrik
authors.affiliation: Center for Health Research and.
authors.forename: David H
authors.initials: DH
authors.lastname: Smith
authors.affiliation: Department of Epidemiology, Biostatistics and Occupational Health, McGill University Health Centre Research Institute, Montreal, Quebec, Canada.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Platt
authors.affiliation: Center for Health Research and.
authors.forename: Eric S
authors.initials: ES
authors.lastname: Johnson
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000419:Albuminuria / Q000652:urine; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure; D048909:Diabetes Complications / Q000453:epidemiology; D005260:Female; D005919:Glomerular Filtration Rate; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D051436:Renal Insufficiency, Chronic / Q000628:therapy*; D017582:Renal Replacement Therapy; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012737:Sex Factors; D013599:Systole; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents; D006454:Hemoglobins
keywords: Antihypertensive Agents; Calibration; Colorado; Fistula; Hemoglobins; Humans; Primary Health Care; Referral and Consultation; Renal Insufficiency; albuminuria; blood pressure; chronic kidney disease; clinical prediction rule; diabetes mellitus; disease progression; glomerular filtration rate; nephrology; prognosis; proteinuria; renal failure; renal insufficiency, chronic; renal replacement therapy; retrospective studies; risk assessment