Table 4.

Baseline characteristics by eGFR level

VariableeGFR (ml/min per 1.73 m2)P
<3030 to <4040 to <5050 to <60≥60
n667844968720397
Age (yr; mean ± SD)58.7 ± 11.259.6 ± 11.060.0 ± 10.457.7 ± 10.151.5 ± 11.00.0001
Gender (n [%])0.0001
    male311 (47)440 (52)568 (59)406 (56)226 (57)
    female356 (53)404 (48)400 (41)314 (44)171 (43)
Racial/ethnic group (n [%])0.0673
    non-Hispanic white277 (42)386 (46)461 (48)348 (48)160 (40)
    non-Hispanic black/African American303 (45)387 (46)430 (44)319 (44)202 (51)
    Hispanic55 (8)43 (5)32 (3)21 (3)18 (5)
    othera32 (5)28 (3)45 (5)32 (4)17 (4)0.0001
Annual household income (n [%])0.1435
    ≤$20,000249 (37)292 (35)232 (24)155 (22)72 (18)
    $20,001 to $50,000179 (27)199 (24)267 (28)162 (23)96 (24)
    $50,001 to $100,000103 (17)150 (18)187 (19)171 (24)108 (27)
    >$100,00038 (6)69 (8)117 (12)115 (16)49 (12)
    no response93 (14)134 (16)165 (17)117 (16)72 (18)
Educational attainment (n [%])0.0001
    <7th grade27 (4)15 (2)10 (1)4 (1)2 (1)
    7th to 12th grade126 (18)160 (19)143 (15)82 (11)27 (7)
    high school diploma145 (22)177 (21)189 (20)112 (16)69 (17)
    vocational degree36 (5)38 (5)48 (5)36 (5)26 (7)
    some college162 (24)224 (27)228 (24)192 (27)112 (28)
    college graduate106 (16)146 (17)188 (19)172 (24)82 (21)
    graduate degree65 (10)84 (10)162 (17)122 (17)76 (19)
Tobacco use (n [%])
    current smoker110 (16)122 (15)117 (12)84 (12)54 (14)0.0001
    >100 cigarettes during lifetime405 (61)500 (59)542 (56)375 (52)139 (48)0.0189
Medical history (n [%])
    hypertension612 (92)767 (91)848 (88)587 (82)267 (67)0.0001
    diabetes352 (53)459 (54)448 (46)290 (40)130 (33)0.0001
    MI or coronary revascularization170 (26)227 (27)227 (23)131 (18)51 (13)0.0001
    chronic heart failure97 (15)103 (12)91 (10)43 (6)19 (5)0.0001
    PAD75 (11)85 (10)47 (5)31 (4)11 (4)0.0001
BP variables.
    SBP (mmHg; mean ± SD)130.5 ± 23.6129.4 ± 23.2127.7 ± 21.3125.4 ± 20.2123.5 ± 20.00.0001
    DBP (mmHg; mean ± SD)69.9 ± 13.370.0 ± 12.671.5 ± 12.772.3 ± 12.374.9 ± 12.80.0001
    MAP (mmHg; mean ± SD)90.1 ± 14.489.8 ± 14.090.2 ± 13.790.0 ± 13.191.1 ± 13.60.6042
    BP >130/80 (mmHg; n [%])335 (50)394 (47)466 (48)319 (45)164 (42)0.0001
Weight (kg; mean ± SD)89.8 ± 24.892.3 ± 23.292.5 ± 23.393.3 ± 24.192.4 ± 22.60.0311
BMI (kg/m2; mean ± SD)31.9 ± 8.432.5 ± 7.932.1 ± 7.832.2 ± 8.131.3 ± 7.10.2313
BMI category (kg/m2; n [%])0.9367
    <25.0134 (20)128 (15)150 (15)121 (17)74 (19)
    25.0 to 29.9182 (27)238 (28)275 (28)206 (29)112 (28)0.0001
    >30353 (53)480 (57)544 (56)392 (55)212 (54)
ABI <0.9142 (22)149 (18)125 (13)93 (13)15 (4)0.0001
Roche adjusted creatinine (mean ± SD)2.56 ± 0.561.90 ± 0.321.56 ± 0.231.32 ± 0.201.14 ± 0.200.0001
Urine protein/24 h (g; median [IQR])0.58 (0.15 to 2.14)0.26 (0.08 to 1.22)0.13 (0.07 to 0.60)0.10 (0.06 to 0.36)0.10 (0.06 to 0.22)0.0001
Lipoproteins
    total cholesterol (mg/dl; mean ± SD)183.3 ± 51.2182.5 ± 46.2183.1 ± 42.1183.2 ± 41.3183.5 ± 39.60.8297
    LDL cholesterol (mg/dl; mean ± SD)99.7 ± 37.9100.2 ± 35.3103.1 ± 34.6104.4 ± 33.3107.3 ± 32.60.0001
    HDL cholesterol (mg/dl; mean ± SD)46.9 ± 15.547.4 ± 15.848.2 ± 14.948.8 ±16.050.2 ± 16.40.0004
    triglycerides (mg/dl; mean ± SD)168.1 ± 127.2163.0 ± 123.4151.4 ± 99.6148.5 ± 127.2129.9 ± 81.60.0001
Hemoglobin (g/dl; mean ± SD)11.8 ± 1.712.3 ± 1.712.8 ± 1.713.2 ± 1.613.4 ± 1.60.0001
Serum calcium (mg/dl; mean ± SD)9.1 ± 0.69.2 ± 0.59.2 ± 0.59.2 ± 0.59.2 ± 0.40.0002
Total iPTH (pg/ml; median [IQR])105.0 (64.0 to 172.0)63.9 (41.0 to 100.0)47.5 (32.0 to 74.0)41.0 (29.7 to 59.1)36.0 (27.3 to 50.3)0.0001
Serum phosphorus(mg/dl; mean ± SD)4.1 ± 0.83.8 ± 0.63.6 ± 0.63.5 ± 0.63.4 ± 0.50.0001
Blood glucose (mg/dl; median [IQR])97.0 (85.0 to 124.0)98.0 (87.0 to 131.0)100.0 (88.0 to 127.0)95.0 (85.0 to 119.0)94.0 (84.0 to 110.0)0.0003
Glycosylated hemoglobin(%; mean ± SD)6.7 ± 1.56.8 ± 1.66.7 ± 1.56.5 ± 1.46.3 ± 1.70.0001
Serum uric acid (mg/dl; mean ± SD)8.2 ± 2.07.9 ± 1.97.3 ± 1.86.8 ± 1.66.2 ± 1.70.0001
  • a Includes Asian/Pacific Islander and Native American individuals.