Table 2.

Comparison of baseline characteristics among patients with and without a baseline phosphate measurementa

Phosphate Measured during 18-Month Baseline Period
Yes (n = 3490)No (n = 3240)
Age, mean (SD)71.2 (10.4)73.4 (9.6)
Race, % (n)
    white74.0 (2583)70.6 (2287)
    black5.8 (203)4.8 (156)
    other1.7 (60)1.4 (46)
    missing18.5 (644)23.2 (751)
Gender, % (n)
    male96.1 (3353)96.4 (3122)
    female3.9 (137)3.6 (118)
Past medical history, % (n)
    diabetes45.2 (1576)39.6 (1284)
    ischemic heart disease60.9 (2124)50.6 (1639)
    congestive heart failure39.9 (1394)26.1 (845)
    cerebrovascular disease13.2 (459)9.5 (307)
    acute renal failure7.0 (243)1.1 (36)
Medication use, % (n)
    ACE inhibitor45.6 (1592)51.2 (1660)
    angiotensin II receptor blocker9.1 (318)7.0 (226)
    statin39.3 (1370)38.2 (1239)
    calcium blocker37.4 (1307)33.3 (1078)
    oral calcium10.7 (375)5.1 (165)
Vital signs, mean (SD)
    body mass indexa29.6 (5.9)29.3 (5.4)
    systolic BP (mmHg)a143.2 (19.4)144.0 (19.0)
    diastolic BP (mmHg)a74.1 (10.8)74.5 (10.6)
Laboratory data, mean (SD)
    creatinine (μmol/L)b180.3 (72.7)163.6 (46.7)
    estimated CrCl (ml/min)b47.2 (18.3)47.5 (15.9)
    albumin (g/L)a38.6 (4.4)39.4 (4)
    hemoglobin (g/L)a131.7 (15.9)136.9 (15.2)
    bicarbonate (mmol/L)a25.8 (2.9)26.5 (2.8)
    calcium (mmol/L)a2.3 (0.1)2.3 (0.1)
  • a Time-averaged values during the 18-mo baseline period.

  • b Cockroft-Gault estimated CrCl from serum creatinine value at the study start date.