Table 1.

Baseline characteristics of 1821 participants in the Korean Cohort Study for Outcome in Patients with CKD

VariableOverall, n=1821Spot Urinary Potassium-to-Creatinine Ratio, mmol/g
Q1<33.99, n=455Q2=33.99–45.94, n=455Q3=45.95–61.69, n=455Q4≥61.70, n=456
Age, median [IQR], yr55 [45–63]53 [40–62]53 [45–63]56 [48–64]56 [48–64]
Men, n (%)1109 (61)352 (77)329 (72)257 (57)171 (38)
BMI, mean (SD), kg/m224.5 (3.4)24.7 (3.5)24.6 (3.5)24.5 (3.2)24.5 (3.4)
Diabetes, n (%)620 (34)171 (8)142 (31)142 (31)165 (36)
Cardiovascular disease, n (%)197 (11)52 (11)44 (10)58 (13)43 (9)
Smoking history, n (%)855 (47)276 (61)256 (56)192 (42)131 (29)
eGFR, median [IQR], ml⋅min−1⋅1.73 m−247 [29–75]38 [24–63]44 [29–68]46 [29–73]58 [36–93]
eGFR, category, ml⋅min−1⋅1.73 m−2, n (%)
 ≥90309 (17)53 (12)65 (14)69 (15)122 (27)
 60–90341 (19)70 (15)81 (18)96 (21)94 (21)
 30–59684 (38)167 (37)189 (42)172 (38)156 (34)
 15–29372 (20)128 (28)92 (20)88 (19)64 (14)
 <15 (nondialysis)115 (6)37 (8)28 (6)30 (7)20 (4)
BUN, median [IQR], mg/dl24 [17–35]27 [18–42]24 [18–35]23 [16–33]21 [15–30]
Hemoglobin, mean (SD), g/dl13 (2)13 (2)13 (2)13 (2)13 (2)
hs-CRP, median [IQR], mg/L0.6 [0.2–1.7]0.7 [0.2–2.0]0.8 [0.3–1.8]0.6 [0.2–1.4]0.5 [0.2–1.6]
Intact PTH, median [IQR], pg/ml51 [33–84]55 [36–99]51 [34–87]54 [36–81]45 [29–71]
Calcium, mean (SD), mg/dl9.1 (0.5)9.1 (0.6)9.1 (0.6)9.1 (0.5)9.2 (0.5)
Albumin, mean (SD), g/dl4.2 (0.4)4.2 (0.4)4.2 (0.5)4.2 (0.4)4.2 (0.4)
Uric acid, mean (SD), mg/dl7.0 (1.9)7.6 (2.0)7.1 (1.8)6.9 (1.8)6.4 (1.7)
Total cholesterol, mean (SD), mg/dl174 (39)167 (38)173 (39)176 (40)179 (36)
LDL cholesterol, mean (SD), mg/dl97 (31)93 (31)97 (32)98 (31)100 (31)
Triglyceride, median [IQR], mg/dl132 [92–192]133 [94–197]134 [91–198]128 [91–189]129 [91–180]
HDL cholesterol, mean (SD), mg/dl50 (16)47 (16)49 (15)50 (15)53 (16)
Serum potassium, mean (SD), mmol/L4.6 (0.6)4.7 (0.6)4.6 (0.6)4.6 (0.6)4.6 (0.5)
 Hyperkalemia (≥5.5 mmol/L), n (%)160 (9)52 (12)37 (9)37 (9)34 (8)
 Normal (3.5–5.4 mmol/L), n (%)1575 (90)386 (88)394 (90)395 (91)400 (92)
 Hypokalemia (<3.5 mmol/L), n (%)11 (0.6)3 (0.6)5 (1)2 (0.5)1 (0.2)
Urinary protein-to-creatinine ratio, median [IQR], g/g0.46 [0.14–1.41]0.51 [0.17–1.53]0.43 [0.12–1.44]0.46 [0.15–1.38]0.44 [0.12–1.29]
Spot urinary Na/Cr, median [IQR]0.88 [0.55–1.32]0.61 [0.32–0.91]0.81 [0.51–1.20]1.02 [0.66–1.38]1.23 [0.85–1.78]
Mean arterial pressure, mean (SD), mm Hg94 (12)93 (12)95 (12)94 (12)93 (11)
Baseline kidney disease, n (%)
 Diabetic nephropathy428 (24)129 (28)101 (22)95 (21)103 (23)
 Hypertensive kidney disease329 (18)82 (18)89 (20)83 (18)75 (16)
 GN633 (35)162 (36)159 (35)153 (34)159 (35)
 Polycystic kidney disease322 (18)59 (13)82 (18)91 (20)90 (20)
 Others109 (6)23 (5)24 (5)33 (7)29 (6)
RAS blocker use, n (%)1553 (85)382 (84)377 (83)396 (87)398 (87)
Diuretics use, n (%)570 (31)174 (38)127 (28)136 (30)133 (29)
Statin use, n (%)938 (52)231 (51)239 (53)241 (53)227 (50)
  • Q, quartile; IQR, interquartile range; BMI, body mass index; hs-CRP, high-sensitivity C-reactive protein; PTH, parathyroid hormone; RAS, renin-angiotensin system.