Table 1.

Patient characteristics (n = 159,720)

CharacteristicAllHemoglobin Variability GroupaP Valueb
L-LI-IH-HL-II-HL-H
Hemoglobin category (<11/11 to 12.5/>12.5)
    Month 122.6/47.7/29.7100/0/00/100/00/0/10038.3/61.7/00/54.6/45.435.3/32.5/32.2
    Month 221.5/48.8/29.8100/0/00/100/00/0/10041.0/59.0/00/51.8/48.231.3/38.5/30.2
    Month 320.6/49.1/30.2100/0/00/100/00/0/10042.3/57.7/00/52.8/47.228.7/39.2/32.1
    Month 419.9/48.4/31.8100/0/00/100/00/0/10042.4/57.6/00/52.5/47.526.7/37.7/35.6
    Month 520.0/49.1/30.9100/0/00/100/00/0/10043.8/56.2/00/55.8/44.226.5/37.4/36.1
    Month 619.2/47.4/33.4100/0/00/100/00/0/10039.2/60.8/00/55.3/44.726.5/31.6/41.9
Gender
    male51.354.054.156.351.052.749.5<0.0001
    female48.746.045.943.749.047.350.6
Race
    white53.448.558.551.354.753.452.4<0.0001
    black40.346.635.041.639.240.341.3
    other6.34.96.57.16.26.36.3
Age, years
     <408.816.87.39.39.67.89.2<0.0001
    40 to 6441.250.139.041.042.840.640.9
    65 to 7426.319.627.226.325.726.726.3
    ≥7523.813.526.623.422.024.923.6
Cause of renal failure
    diabetes42.835.143.442.442.742.943.0<0.0001
    hypertension29.827.328.430.428.530.530.0
    other27.437.628.227.328.826.727.0
Dialysis vintage, yr
     <120.518.714.028.216.121.422.3<0.0001
    1 to <331.527.235.927.532.331.730.8
    3 to <520.819.622.917.922.120.720.2
    ≥527.234.527.326.529.626.326.7
  • a Monthly hemoglobin values were categorized as low (L, <11 g/dl), intermediate (I, 11 to 12.5 g/dl), and high (H, >12.5 g/dl); variability groups were classified on the basis of the lowest and highest categories seen in the 6-mo observation period. Values are percents.

  • b χ2 test.