Table 2

Patient characteristics for the whole population and separate per CKD stage

Overall (n=3132)CKD 3a (n=843)CKD 3b (n=1125)CKD 4 (n=862)CKD 5 (n=302)Chi2
N (%)Mean (±SD)N (%)Mean (±SD)N (%)Mean (±SD)N (%)Mean (±SD)N (%)Mean (±SD)p-value
Age (years)67.7 (±14.1)63.1 (±14.2)68.9 (±13.2)70.2 (±13.8)69.2 (±14.8)
 <50 years363 (11.6)151 (17.9)113 (10.0)70 (8.1)29 (9.6)
 50–80 years2149 (68.6)604 (71.7)793 (70.5)556 (64.5)196 (64.9)
 >=80 years620 (19.8)88 (10.4)219 (19.5)236 (27.4)77 (25.5)
Gender (males)1738 (55.5)456 (54.1)614 (54.6)488 (56.6)180 (59.6)0.314
Diabetes (yes)485 (15.5)96 (11.4)166 (14.8)165 (19.1)58 (19.2)<0.001
eGFR (MDRD) (ml/min/1.73 m23132 (100)35 [24-46]*843 (100)52.2 (±4.3)1125 (100)37.3 (±4.2)862 (100)23.1 (±4.3)302 (100)11.1 (±2.6)
SBP (mm Hg)2511 (80.2)132.0 (±18.8)601 (71.3)129.4 (±17.3)910 (80.9)130.7 (±18.6)735 (85.3)133.3 (±19.4)265 (87.7)139.1 (±19.2)<0.001
Elevated SBP (>140 mm Hg)700 (22.3)155.3 (±12.4)119 (14.1)155.3 (±12.3)239 (21.2)154.3 (±12.5)233 (27.0)155.4 (±12.2)109 (36.1)157.1 (±12.6)
DBP (mm Hg)2511 (80.2)75.1 (±11.2)601 (71.3)76.7 (±10.6)910 (80.9)74.9 (±11.3)735 (85.3)74.6 (±11.2)265 (87.7)74.0 (±12.1)<0.001
Low DBP (<70 mm Hg)704 (22.5)61.6 (±5.8)130 (15.4)62.1 (±5.5)282 (25.1)62.1 (±5.4)214 (24.8)61.3 (±6.1)78 (25.8)59.4 (±6.5)
Total protein (g/24 h urine)1314 (42.0)0.4 (0.1–1.3]*278 (33.0)0.3 (0.1–0.8]*426 (37.9)0.2 (0.1–0.8]*403 (46.8)0.4 (0.2–1.3]*207 (68.5)1.3 (0.5–2.8]*<0.001
Total protein (g/L urine)2328 (74.3)0.2 (0.1–0.6]*552 (65.5)0.1 (0.1–0.3]*841 (74.8)0.2 (0.1–0.4]*687 (79.7)0.3 (0.1–0.6]*248 (82.1)0.8 (0.3–1.7]*<0.001
Proteinuria (>0.5 g/24 h or l urine)810 (25.9)140 (16.6)224 (19.9)268 (31.1)178 (58.9)
Phosphate (mmol/L)2606 (83.2)1.08 (±0.29)539 (63.9)0.96 (±0.20)959 (85.2)1.00 (±0.20)815 (94.5)1.10 (±0.25)293 (97.0)1.48 (±0.39)<0.001
Elevated phosphate (>1.49 mmol/L)172 (5.5)1.80 (±0.34)3 (0.4)1.69 (±0.22)17 (1.5)1.65 (±0.20)41 (4.8)1.72 (±0.32)111 (36.8)1.85 (±0.36)
Calcium (mmol/L)2734 (87.3)2.36 (±0.14)616 (73.1)2.38 (±0.11)998 (88.7)2.37 (±0.13)822 (95.4)2.35 (±0.15)298 (98.7)2.30 (±0.16)<0.001
Elevated calcium (>2.54 mmol/L)163 (5.2)2.62 (±0.08)40 (4.7)2.61 (±0.08)61 (5.4)2.62 (±0.09)46 (5.3)2.62 (±0.06)16 (5.3)2.64 (±0.08)
Haemoglobin (mmol/L)3024 (96.6)8.0 (±1.1)771 (91.5)8.5 (±1.1)1095 (97.3)8.2 (±1.0)857 (99.4)7.7 (±1.1)301 (99.7)7.0 (±0.9)<0.001
Low haemoglobin level (<7.5 mmol/L)933 (29.8)6.7 (±0.6)113 (13.4)6.8 (±0.6)264 (23.5)6.8 (±0.5)346 (40.1)6.7 (±0.6)210 (69.5)6.6 (±0.7)
Clinic<0.001
 A569 (18.2)92 (10.9)166 (14.8)183 (21.2)128 (42.4)
 B845 (27.0)255 (30.3)295 (26.2)219 (25.4)76 (25.2)
 C1718 (54.9)496 (58.8)664 (59.0)460 (53.4)98 (32.5)
  • *Median with IQR.

  • CKD, chronic kidney disease; clinics A and B: university nephrology outpatient clinics; clinic C: non-university nephrology outpatient clinic ; DBP, diastolic blood pressure; eGFR, estimated glomerular filtration rate; MDRD, modification of diet in renal disease; SBP, systolic blood pressure.