title: Albuminuria as a Risk Factor for Anemia in Chronic Kidney Disease: Result from the KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD).
abstract: BACKGROUND
  Anemia is a common complication among patients with chronic kidney disease (CKD), and it is associated with unfavorable clinical outcomes in patients with CKD independent of the estimated glomerular filtration rate (eGFR). We assessed the association of the urinary albumin-to-creatinine ratio (ACR) and eGFR with anemia in CKD patients.
  
  
  METHODS
  We conducted a cross-sectional study using baseline data from the KoreaN Cohort Study for Outcome in Patients With Chronic Kidney Disease (KNOW-CKD). Multiple regression analysis was performed to identify the independent association of albuminuria with anemia. Furthermore, odds ratios for anemia were calculated by cross-categorization of ACR and eGFR.
  
  
  RESULTS
  Among 1,456 patients, the mean age was 53.5 ± 12.4 years, and the mean eGFR and ACR were 51.9 ± 30.5 mL/min per 1.73 m2 and 853.2 ± 1,330.3 mg/g, respectively. Anemia was present in 644 patients (40.5%). Multivariate analysis showed that the odds ratio of anemia increased according to ACR levels, after adjusting for age, sex, eGFR, body mass index, pulse pressure, cause of CKD, use of erythropoiesis stimulating agents, serum calcium and ferritin (ACR < 30 mg/g as a reference group; 30-299 mg/g, adjusted odds ratio (OR) = 1.43, 95% confidence interval (CI) = 0.88-2.33; ≥300 mg/g, adjusted OR = 1.86, 95% CI = 1.12-3.10). In addition, graded associations were observed in cross-categorized groups of a higher ACR and eGFR compared to the reference group with an ACR <30 mg/g and eGFR ≥60 mL/min per 1.73 m2.
  
  
  CONCLUSIONS
  The present study demonstrated that albuminuria was a significant risk factor for anemia in CKD patients independent of the eGFR.
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Ji Suk
authors.initials: JS
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Mi Jung
authors.initials: MJ
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Kyoung Sook
authors.initials: KS
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Seung Hyeok
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Tae-Hyun
authors.initials: TH
authors.lastname: Yoo
authors.affiliation: Department of Internal Medicine, Seoul National University, Seoul, Korea.
authors.forename: Kook-Hwan
authors.initials: KH
authors.lastname: Oh
authors.affiliation: Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Sue Kyung
authors.initials: SK
authors.lastname: Park
authors.affiliation: Medical Research Collaborating Center, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Joongyub
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Medical Center, Sungkyunkwan University, Seoul, Korea.
authors.forename: Young Youl
authors.initials: YY
authors.lastname: Hyun
authors.affiliation: Department of Internal Medicine, Gachon University, Gil Hospital, Incheon, Korea.
authors.forename: Wookyung
authors.initials: W
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Inje University, Pusan Paik Hospital, Busan, Korea.
authors.forename: Yeong Hoon
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University, Seoul, Korea.
authors.forename: Curie
authors.initials: C
authors.lastname: Ahn
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Kyu Hun
authors.initials: KH
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000150:complications*; D000740:Anemia / Q000150:complications*; D015331:Cohort Studies; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications*; D008875:Middle Aged; D056910:Republic of Korea; D012307:Risk Factors; D016896:Treatment Outcome