Table 1.
Clinicodemographic characteristics, biochemical parameters, and vascular assessments according to CKD stages
| Parameters | Stage 1 (≥90 ml/min; n=79) | Stage 2 (60–89 ml/min; n=78) | Stage 3 (30–59 ml/min; n=80) | Stage 4 (15–29 ml/min; n=82) | Stage 5 (<15 ml/min; n=84) | P Valuea |
|---|---|---|---|---|---|---|
| Age, yr | 50 (28–71) | 56 (30–71) | 52 (29–71) | 55 (31–73) | 53 (28–71) | 0.31 |
| Sex (men/women) | 45/34 | 46/32 | 46/34 | 40/42 | 51/33 | 0.59 |
| Body mass index, kg/m2 | 26.6±2.2 | 26.3±3.1 | 25.9±2.4 | 26.2±2.9 | 25.4±2.8 | 0.06 |
| History of CV disease, n | ||||||
| CV episode | 9 (11%) | 3 (4%) | 10 (13%) | 12 (15%) | 20 (24%) | 0.02 |
| Stroke | 3 (4%) | 2 (3%) | 1 (1%) | — | 3 (4%) | 0.08 |
| Peripheral vascular disease | 4 (5%) | 1 (1%) | — | 2 (3%) | 3 (4%) | 0.07 |
| Aortic aneurysm | 3 (4%) | 1 (1%) | — | — | — | 0.11 |
| Etiology of CKD, n | ||||||
| Diabetes | 12 (15%) | 22 (28%) | 17 (21%) | 20 (24%) | 20 (24%) | 0.38 |
| GN | 11 (14%) | 9 (12%) | 13 (16%) | 11 (13%) | 13 (15%) | 0.67 |
| Hypertension | 9 (12%) | 19 (24%) | 16 (20%) | 10 (12%) | 10 (12%) | 0.08 |
| Polycystic kidney disease | 5 (6%) | 2 (3%) | 3 (4%) | 4 (5%) | 2 (2%) | 0.23 |
| Reflux nephropathy | 3 (4%) | 3 (4%) | 1 (1%) | 4 (5%) | 2 (2%) | 0.13 |
| Amyloidosis | 4 (5%) | 6 (8%) | 4 (5%) | 5 (6%) | 5 (6%) | 0.68 |
| Unknown | 35 (44%) | 17 (22%) | 26 (33%) | 28 (34) | 32 (38%) | 0.72 |
| Smoking (current), n | 37 (47%) | 37 | 36 (45%) | 32 (39%) | 41 (49%) | 0.15 |
| Total cholesterol, mg/dl | 200 (160–239) | 202 (170–243) | 200 (171–245) | 199 (159–244) | 195 (157–243) | 0.10 |
| Triglycerides, mg/dl | 142±15 | 144±12 | 147±16 | 145±14 | 142±20 | 0.20 |
| LDL cholesterol, mg/dl | 128±17 | 131±16 | 126±15 | 129±14 | 123±21 | 0.04 |
| Systolic BP, mmHg | 135±9 | 138±12 | 135±13 | 136±15 | 134±10 | 0.10 |
| Diastolic BP, mmHg | 83±4 | 84±3 | 85±4 | 84±6 | 84±5 | 0.07 |
| Serum calcium, mg/dl | 8.9±0.5 | 8.7±0.5 | 8.3±0.5 | 8.1±0.4 | 8.1±0.4 | <0.001 |
| Serum phosphate, mg/dl | 4.1±0.4 | 4.3±0.9 | 4.6±0.8 | 5.7±1.3 | 6.6±1.6 | <0.001 |
| iPTH, pg/ml | 51±12 | 70±28 | 152±42 | 167±33 | 257±41 | <0.001 |
| Serum albumin, g/dl | 4.0 (3.6–4.8) | 4.0 (3.5–4.6) | 4.3 (3.5–4.8) | 4.0 (3.4–4.6) | 3.9 (3.2–4.6) | <0.001 |
| HOMA-IR index | 1.64±0.72 | 1.78±0.61 | 1.89±1.08 | 1.96±1.00 | 1.86±0.95 | 0.20 |
| 24-h proteinuria, g/d | 1.39 (0.38–2.45) | 1.68 (0.37–3.92) | 1.71 (0.57–5.15) | 1.57 (0.48–4.39) | 1.7 (0.8–5.45) | <0.001 |
| hsCRP, mg/L | 8.0 (3.2–13.6) | 11.2 (5.0–16.0) | 17.0 (5.0–22.0) | 23.0 (6.7–35.0) | 25.5 (4.0–44.0) | <0.001 |
| PTX-3, ng/ml | 3.6 (1.3–45.2) | 6.9 (1.4–42.8) | 8.41 (0.5–60.5) | 9.15 (0.6–48.7) | 15.2 (0.8–67.3) | <0.001 |
| IL-6, pg/ml | 5.2 (1.0–6.6) | 5.5 (1.0–7.3) | 6.1 (1.0–12.6) | 7.4 (1.0–15.4) | 12.0 (1.3–27.4) | <0.001 |
| IL-10, pg/ml | 9.7 (2.1–47.2) | 12.0 (2.2–59.0) | 16.8 (3.6–58.7) | 32.5 (3.2–62.6) | 41.5 (5.6–66.0) | <0.001 |
| IL-6/IL-10 ratio | 0.47 (0.03–2.18) | 0.33 (0.03–2.54) | 0.30 (0.02–2.52) | 0.20 (0.02–2.27) | 0.23 (0.02–2.18) | <0.001 |
| NMD, % | 13.0 (11.0–13.8) | 13.1 (12.4–13.8) | 12.9 (12.0–13.9) | 13.0 (11.6–13.8) | 12.2 (10.0–13.1) | <0.001 |
| FMD, % | 8.4±0.7 | 7.3±0.6 | 7.0±0.7 | 6.4±0.8 | 5.7±1.0 | <0.001 |
Units for CKD stages are presented as ml/min per 1.73 m2. CV, cardiovascular; iPTH, intact parathyroid hormone; HOMA-IR, Homeostasis Model Assessment–Insulin Resistance; hsCRP, high-sensitivity C-reactive protein; PTX-3, pentraxin-3; NMD, nitroglycerine-mediated dilatation; FMD, flow-mediated dilatation.
a
Differences assessed by chi-squared test for categorical variables and Kruskal–Wallis test. Statistically significant if P<0.05.