Table 3.
Baseline Characteristics of the Study Participants Stratified by IBI Quartile
| Variables | Total (n = 3225) | Q1 | Q2 | Q3 | Q4 | p value |
|---|---|---|---|---|---|---|
| ≤4.99 | 4.99–13.95 | 13.95–34.12 | ≥34.12 | |||
| (n = 806) | (n = 806) | (n = 807) | (n = 806) | |||
| Sex, female (%) | 1435 (44.5) | 390 (48.4) | 380 (47.1) | 339 (42) | 326 (40.4) | 0.002* |
| Age (years) | 52.6 ± 14.8 | 49.5 ± 14.5 | 52.1 ± 14.1 | 52.5 ± 14.9 | 56.1 ± 14.9 | < 0.001* |
| BMI (kg/m2) | 22.3 ± 3.4 | 21.8 ± 3.2 | 22.4 ± 3.5 | 22.5 ± 3.5 | 22.5 ± 3.4 | < 0.001* |
| Smoking, n (%) | 276 (8.6) | 55 (6.8) | 51 (6.3) | 76 (9.4) | 94 (11.7) | <0.001* |
| Alcohol consumption, n (%) | 75 (2.3) | 10 (1.2) | 16 (2) | 24 (3) | 25 (3.1) | 0.042* |
| Diabetes, n (%) | 1103 (34.2) | 263 (32.6) | 287 (35.6) | 277 (34.3) | 276 (34.2) | 0.660 |
| CVD, n (%) | 944 (29.3) | 205 (25.4) | 226 (28) | 246 (30.5) | 267 (33.1) | 0.005* |
| Systolic pressure (mmHg) | 146.1 ± 23.7 | 143.9 ± 21.6 | 146.2 ± 24.0 | 146.7 ± 24.0 | 147.7 ± 25.0 | 0.012* |
| Diastolic pressure (mmHg) | 85.2 ± 15.3 | 85.0 ± 14.7 | 85.0 ± 15.0 | 85.6 ± 15.3 | 85.0 ± 16.1 | 0.782 |
| Medication | ||||||
| CCB, n (%) | 2027 (62.9) | 501 (62.2) | 511 (63.4) | 511 (63.3) | 504 (62.5) | 0.944 |
| ACEI, n (%) | 781 (24.2) | 205 (25.4) | 180 (22.3) | 204 (25.3) | 192 (23.8) | 0.428 |
| ARB, n (%) | 936 (29.0) | 246 (30.5) | 229 (28.4) | 242 (30) | 219 (27.2) | 0.435 |
| β-blocker, n (%) | 1112 (34.5) | 285 (35.4) | 275 (34.1) | 295 (36.6) | 257 (31.9) | 0.235 |
| ɑ-blocker, n(%) | 670 (20.8) | 187 (23.2) | 163 (20.2) | 171 (21.2) | 149 (18.5) | 0.128 |
| Diuretic, n(%) | 175 (5.4) | 42 (5.2) | 40 (5) | 51 (6.3) | 42 (5.2) | 0.628 |
| Aspirin, n (%) | 236 (7.3) | 61 (7.6) | 53 (6.6) | 60 (7.4) | 62 (7.7) | 0.823 |
| Laboratory variables | ||||||
| White blood cell (10^9/L) | 6.79 ± 2.34 | 6.20 ± 1.89 | 6.52 ± 2.18 | 6.71 ± 2.03 | 7.70 ± 2.87 | < 0.001* |
| Platelet (10^9/L) | 203.8 ± 70.1 | 204.1 ± 65.9 | 200.9 ± 66.5 | 201.8 ± 70.5 | 208.4 ± 76.7 | 0.143 |
| Hemoglobin (g/L) | 96.4 ± 19.8 | 98.6 ± 21.0 | 95.7 ± 18.6 | 96.4 ± 20.0 | 94.9 ± 19.3 | 0.001* |
| Neutrophils (10^9/L) | 4.62 ± 2.02 | 3.89 ± 1.54 | 4.35 ± 1.79 | 4.56 ± 1.70 | 5.67 ± 2.50 | < 0.001* |
| Monocytes (10^9/L) | 0.50 ± 0.26 | 0.49 ± 0.29 | 0.48 ± 0.25 | 0.50 ± 0.25 | 0.53 ± 0.25 | 0.006* |
| Lymphocytes (10^9/L) | 1.31 ± 0.53 | 1.45 ± 0.50 | 1.36 ± 0.54 | 1.31 ± 0.53 | 1.14 ± 0.52 | < 0.001* |
| Glucose (mmol/L) | 5.43 ± 2.14 | 5.23 ± 1.81 | 5.36 ± 2.25 | 5.45 ± 2.16 | 5.67 ± 2.29 | < 0.001* |
| Albumin (g/L) | 34.8 ± 5.6 | 36.0 ± 5.6 | 34.9 ± 5.5 | 34.6 ± 5.5 | 33.7 ± 5.5 | < 0.001* |
| Uric acid (mmol/L) | 416.7 ± 113.8 | 412.8 ± 110.6 | 421.3 ± 117.2 | 412.5 ± 112.3 | 420.0 ± 115.0 | 0.255 |
| Cholesterol (mmol/L) | 4.65 ± 1.34 | 4.70 ± 1.34 | 4.63 ± 1.32 | 4.65 ± 1.38 | 4.60 ± 1.30 | 0.504 |
| Triglyceride (mmol/L) | 1.70 ± 1.37 | 1.64 ± 1.31 | 1.66 ± 1.29 | 1.79 ± 1.54 | 1.71 ± 1.31 | 0.151 |
| Calcium (mmol/L) | 2.11 ± 0.28 | 2.14 ± 0.28 | 2.10 ± 0.26 | 2.11 ± 0.28 | 2.08 ± 0.30 | < 0.001* |
| Phosphorus (mmol/L) | 1.65 ± 0.56 | 1.67 ± 0.55 | 1.66 ± 0.53 | 1.65 ± 0.54 | 1.63 ± 0.60 | 0.619 |
| Intact Parathyroid hormone (pg/mL) | 326.3 ± 259.2 | 343.5 ± 278.9 | 333.6 ± 268.6 | 315.8 ± 243.2 | 312.4 ± 243.6 | 0.049* |
| CRP (mg/L) | 6.66 ± 7.23 | 0.95 ± 0.71 | 3.06 ± 1.74 | 7.07 ± 3.77 | 15.53 ± 8.18 | < 0.001* |
| eGFR (mL/min/1.73m2) | 6.82 ± 3.08 | 6.71 ± 3.05 | 6.81 ± 3.15 | 6.84 ± 3.07 | 6.93 ± 3.05 | 0.554 |
| Kt/V | 2.13 ± 0.59 | 2.17 ± 0.55 | 2.15 ± 0.60 | 2.09 ± 0.61 | 2.11 ± 0.59 | 0.034* |
Note: Continuous variables are shown as the mean ± SD or median (IQR). Bold formatting and *: p < 0.05.
Abbreviations: BMI, body mass index; CVD, cardiovascular disease; CCB, calcium channel blocker; ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; CRP, C-reactive protein; eGFR, estimated glomerular; Kt/V, K dialyzer clearance of urea.