Table 1.

Baseline characteristics of patients who were treated with phosphorus binders versus those who were untreated in the overall unmatched cohort and the propensity score–matched cohorta

CharacteristicUnmatched CohortPPropensity Score–Matched Cohort
Treated(n = 3555)Untreated(n = 5055)Treated(n = 3186)Untreated(n = 3186)P
Age (yr; mean [SD])60 (16)65 (15)<0.000161 (16)62 (15)0.01
Female (%)45.445.60.8946.745.10.21
Race/ethnicity (%)
    black32.731.70.3133.433.10.83
    Hispanic12.213.80.0312.012.70.36
Cause of renal failure (%)
    diabetes42.744.00.0143.143.70.98
    hypertension35.735.135.735.0
    glomerulonephritis10.48.510.110.0
    other11.312.411.111.2
Systolic BP (mmHg; mean [SD])146 (22)143 (23)<0.0001146 (22)146 (23)0.63
BMI (kg/m2; mean [SD])28 (8)27 (9)<0.000128 (8)28 (9)0.41
Initial vascular access (%)
    fistula26.722.6<0.000126.925.50.39
    graft10.111.310.610.8
    catheter58.962.858.560.1
Laboratory tests (mean [SD])
    albumin (g/dl)3.5 (0.5)3.4 (0.5)0.143.5 (0.5)3.5 (0.5)0.36
    creatinine (mg/dl)6.8 (2.8)5.9 (2.6)<0.00016.6 (2.8)6.5 (2.6)0.09
    calcium (mg/dl)8.4 (0.9)8.4 (0.8)0.308.4 (0.9)8.4 (0.9)0.59
    phosphate (mg/dl)5.0 (1.7)4.5 (1.4)<0.00014.8 (1.6)4.8 (1.5)0.15
    PTH (pg/ml; median [IQR])223 (123 to 384)195 (105 to 331)0.009216 (119 to 375)210 (115 to 355)0.13
    hemoglobin (g/dl)10.3 (1.4)10.4 (1.4)0.00310.3 (1.4)10.3 (1.4)0.84
Vitamin D therapy (% treated at initiation)11.811.10.3311.812.00.82
  • a The treated group included patients who began treatment during the first 90 d on hemodialysis, whereas the untreated group included those who were not treated during the first 90 d. IQR, interquartile range. BMI, body mass index.