Table 1.
Baseline demographic, clinical and biochemical characteristics, and outcomes of the study population, stratified by tertiles of plasma calprotectin levels
| Characteristics | Total | T1 | T2 | T3 | P-value |
|---|---|---|---|---|---|
| ♂: <0.42 μg/l ♀: <0.38 μg/l |
♂: 0.42–0.62 μg/l ♀: 0.38–0.59 μg/l |
♂: >0.62 μg/l ♀: >0.59 μg/l |
|||
| Plasma calprotectin (μg/l) | 0.49 [0.35–0.68] | 0.30 [0.24–0.35] | 0.49 [0.44–0.53] | 0.78 [0.68–0.98] | |
| Demographics | |||||
| Age (yr) | 51.4 ± 11.4 | 50.2 ± 11.3 | 51.4 ± 11.1 | 52.5 ± 11.6 | <0.001 |
| Women, n (%) | 2514 (53.9) | 938 (59.8) | 775 (51.4) | 801 (50.5) | <0.001 |
| Race, n (%) | 0.003 | ||||
| White, n (%) | 4441 (96.0) | 1463 (94.4) | 1448 (96.6) | 1530 (96.8) | |
| Black, n (%) | 42 (0.9) | 15 (1.0) | 10 (0.7) | 17 (1.1) | |
| Asian, n (%) | 94 (2.0) | 47 (3.0) | 28 (1.9) | 19 (1.2) | |
| Other, n (%) | 51 (1.1) | 24 (1.5) | 13 (0.9) | 14 (0.9) | |
| Anthropometrics | |||||
| BMI (kg/m2) | 25.7 [23.4–28.4] | 24.7 [22.6–27.5] | 25.8 [23.6–28.5] | 26.5 [24.2–29.2] | <0.001 |
| Waist circumference (cm) | 90 [81–98] | 86 [78–95] | 91 [82–99] | 92 [84–101] | <0.001 |
| Cardiovascular risk factors | |||||
| SBP (mm Hg) | 120 [111–133] | 117 [108–128] | 122 [112–133] | 124 [113–136] | <0.001 |
| DBP (mm Hg) | 72 [66-78] | 70 [65–76] | 72 [67–78] | 73 [68–79] | <0.001 |
| Smoking | <0.001 | ||||
| Never, n (%) | 1448 (31.5) | 561 (36.3) | 485 (32.5) | 402 (25.7) | |
| Current, n (%) | 1283 (27.9) | 310 (20.0) | 387 (25.9) | 586 (37.5) | |
| Former, n (%) | 1872 (40.7) | 676 (43.7) | 621 (41.6) | 575 (36.8) | |
| History of CVD, n (%) | 123 (2.6) | 32 (2.0) | 44 (2.9) | 47 (3.0) | 0.193 |
| Diabetes, n (%) | 68 (1.5) | 16 (1.0) | 18 (1.2) | 34 (2.2) | 0.018 |
| Hypertension, n (%) | 1168 (25.1) | 317 (20.2) | 376 (24.9) | 475 (30.0) | <0.001 |
| Medication | |||||
| Antihypertensive drugs, n (%) | 626 (13.8) | 174 (11.4) | 192 (13.1) | 260 (16.9) | <0.001 |
| Lipid-lowering drugs, n (%) | 272 (5.8) | 68 (4.3) | 97 (6.4) | 107 (6.8) | 0.007 |
| Glucose-lowering drugs, n (%) | 39 (1.0) | 8 (0.6) | 13 (1.0) | 18 (1.3) | 0.143 |
| Laboratory measurements | |||||
| Total cholesterol (mmol/l) | 5.36 [4.72–6.10] | 5.25 [4.60–6.00] | 5.31 [4.69–6.07] | 5.50 [4.84–6.22] | <0.001 |
| hs-CRP (mg/l) | 1.16 [0.56–2.65] | 0.73 [0.34–1.44] | 1.12 [0.61–2.37] | 2.14 [1.01–4.35] | <0.001 |
| Baseline eGFR (ml/min per 1.73 m2) | 95.9 [85.0–105.7] | 97.8 [86.9–107.4] | 96.1 [85.2–105.5] | 94.1 [82.2–103.5] | <0.001 |
| Baseline UAE (mg/l) | 7.68 [5.78–11.2] | 7.16 [5.67–10.2] | 7.75 [5.76–11.1] | 8.13 [5.96–12.3] | <0.001 |
| Serum creatinine (μmol/l) | 81.1 [72.9–90.4] | 80.1 [71.9–89.3] | 82.1 [72.9–91.4] | 82.1 [73.9–92.4] | <0.001 |
| Urine creatinine (mmol/24h) | 11.9 [9.91–14.5] | 11.6 [9.83–14.2] | 12.0 [10.1–14.7] | 12.1 [9.91–14.7] | <0.001 |
| New-onset CKD after follow-up | |||||
| CKD (eGFR <60 ml/min per 1.73 m2), n (%) | 151 (3.2) | 38 (2.4) | 48 (3.2) | 65 (4.1) | 0.026 |
| CKD (UAE >30 mg/24h), n (%) | 349 (7.5) | 98 (5.3) | 109 (7.2) | 142 (9.0) | 0.012 |
| CKD (combined), n (%) | 467 (10.0) | 132 (8.4) | 144 (9.5) | 191 (12.1) | 0.002 |
BMI, body-mass index; CKD, chronic kidney disease; CVD, cardiovascular disease; DBP, diastolic blood pressure; eGFR, estimated glomerular filtration rate; hs-CRP, high-sensitive C-reactive protein; SBP, systolic blood pressure; UAE, urinary albumin excretion.