Table 2.

Comparison of participants across the four quartiles of the erythropoietin-response measure distribution.

VariableQuartile of Erythropoietin Response
1 (low)234 (high)
Mortality (%)a34282514
Age (yr)64 ± 264 ± 1264 ± 1267 ± 11
    <456894
    45–5926302818
    60–7448444653
    ≥7520191726
Gender, female (%)54515649
Diabetes mellitus (%)58545451
Race, ethnicity (%)
    white41514845
    black45393640
    other14101615
Time on dialysis (yr)
    <1 yr31222630
    1-<341333741
    3-<514182113
    >514281616
Vascular access (%)
    graft66626868
    natural fistula20272024
    other/not specified1411129
Current hypertension (%)76696275
Peripheral vascular disease (%)40414237
Cardiac-related hospitalizations (%)66835860
New York Heart Disease Association class (%)
    I26373230
    II55444252
    III19192618
Hematocrit (%)30.4 ± 3.030.4 ± 2.630.6 ± 2.930.3 ± 3.0
Epoetin alfa dose (U/kg per wk)b132 ± 100209 ± 119183 ± 87133 ± 83
Albumin (g/L)37.6 ± 3.437.9 ± 3.636.9 ± 4.237.2 ± 3.4
Creatinine (μ mol/L)822 ± 301902 ± 283859 ± 256822 ± 239
Transferrin saturation (%)27.5 ± 15.426.3 ± 11.725.3 ± 13.125.4 ± 11.6
White blood cell count (× 109/L)7.0 ± 2.36.8 ± 1.77.1 ± 2.47.0 ± 2.2
Lymphocytes (% of white blood cell count)22.7 ± 10.321.3 ± 7.7624.7 ± 10.724.1 ± 9.1
Erythropoietin-response (% hematocrit/wk per 1000 IU Epoetin alfa)b−0.38 ± 0.370.05 ± 0.050.20 ± 0.050.56 ± 0.39
  • Categorical data are percentages and continuous measures are mean ± standard deviation (SD).

  • a P = 0.03; P (trend) = 0.004.

  • b P < 0.0001.