Table 1.

Baseline characteristics of 36,757 patients on incident hemodialysis according to renal CLurea-corrected nPCR level

VariableTotal, n=36,757renal CLurea-corrected nPCR at baselineStd Diff.
<1.2, n=29,685≥1.2, n=7072
Baseline nPCR, g/kg per day0.94 (0.77–1.14)0.87 (0.73–1.01)1.35 (1.27–1.50)2.95
Age, yr62±1562±1561±140.08
Women, %3739290.21
Race/ethnicity, %
 Non-Hispanic white5454540.01
 Black2830190.27
 Hispanic1110160.20
 Asian3370.19
 Others3350.07
ESRD reason, %
 Diabetes4746480.04
 Hypertension2829260.05
 GN1010110.03
 Cystic kidney disease2220.04
 Others1313130.02
Access type, %
 Central venous catheter7475710.09
 AV fistula1817220.12
 AV graft4430.04
 AV other<0.1<0.1<0.10.00
 Unknown4440.00
Comorbidity, %
 Hypertension5051480.06
 Atherosclerotic heart disease1414140.01
 Congestive heart failure3838370.01
 Cerebrovascular disease2210.04
 Other cardiovascular disease1516140.03
 History of cancer2320.02
 HIV0.40.40.40.02
 COPD5540.04
 Dyslipidemia2626270.02
spKt/V1.55±0.361.53±0.351.66±0.390.37
Body mass index, kg/m227.4 (23.6–32.7)27.5 (23.7–32.9)26.9 (23.4–31.9)0.08
Renal CLurea, ml/min per 1.73 m22.92 (1.54–4.76)2.62 (1.36–4.30)4.38 (2.74–6.42)0.70
Laboratories
 WBC, 1000/μl7.5 (6.1–9.0)7.5 (6.1–9.0)7.5 (6.2–9.0)0.03
 Lymphocyte, %21±721±720±70.09
 Hemoglobin, g/dl11.2±1.111.2±1.111.4±1.10.21
 Albumin, g/dl3.57±0.463.54±0.463.69±0.410.34
 Corrected calcium, mg/dl9.1±0.59.1±0.59.0±0.60.14
 Phosphorus, mg/dl5.0±1.14.9±1.15.3±1.20.34
 Intact PTH, pg/ml314 (202–479)310 (199–478)328 (216–482)0.07
 ALP, IU/L84 (67–110)85 (68–111)81 (64–105)0.15
 Creatinine, mg/dl5.9±2.45.8±2.36.1±2.40.14
 TIBC, mg/dl230 (201–260)227 (198–257)241 (214–271)0.35
 Transferrin saturation, %23±823±823±80.11
 Ferritin, ng/ml268 (157–451)269 (157–453)268 (156–445)0.01
 Bicarbonate, mEq/L23.5±2.623.7±2.622.7±2.60.37
  • Continuous values are expressed as mean±SD if normally distributed or median (interquartile range) if skewed. Differences in patient characteristics between two groups were compared by Std Diff., of which 0.8, 0.5, and 0.2 were considered large, medium, and small differences, respectively, and ≥0.1 was defined as meaningful imbalance. nPCRdial+renal, normalized protein catabolic ratedialysis+renal; Std Diff., standardized difference; nPCR, normalized protein catabolic rate; AV, arteriovenous; COPD, chronic obstructive pulmonary disease; spKt/V, single-pool Kt/V; CLurea, urea clearance; WBC, white blood cell; PTH, parathyroid hormone; ALP, alkaline phosphatase; TIBC, total iron binding capacity.