Table 2.
Baseline characteristics in relation to tertile stratification of fiber intake densitya
| Variables | Fiber intake density stratified by tertile |
P for trend | ||
|---|---|---|---|---|
| Upper (n = 73) | Middle (n = 73) | Lowest (n = 73) | ||
| Clinical and demographic | ||||
| Age (yr) | 54.4 ± 12.0 | 55.4 ± 11.9 | 56.8 ± 11.1 | 0.5 |
| Men, n (%) | 36 (51.4) | 38 (50.7) | 35 (47.3) | 0.9 |
| Diabetes mellitus, n (%) | 22 (31.4) | 26 (34.7) | 18 (24.3) | 0.4 |
| Positive smoking history, n (%) | 18 (25.7) | 19 (25.3) | 16 (21.6) | 0.9 |
| Body mass index (kg/m2) | 23.6 ± 4.05 | 22.5 ± 2.87 | 23.1 ± 3.17 | 0.1 |
| Duration of dialysis (mo)b | 24 (13, 27) | 25 (13, 50) | 39 (19, 60) | 0.03 |
| Systolic BP (mm Hg) | 144 ± 16 | 149 ± 18 | 146 ± 17 | 0.3 |
| Diastolic BP (mm Hg) | 81 ± 10 | 84 ± 10 | 81 ± 9 | 0.1 |
| Pulse pressure (mm Hg) | 63 ± 13 | 65 ± 14 | 65 ± 14 | 0.7 |
| Hypertension, n (%) | 56 (80) | 66 (88) | 66 (89.2) | 0.2 |
| Background AVD, n (%) | 18 (25.7) | 19 (25.3) | 15 (20.3) | 0.7 |
| Coronary artery disease, n (%) | 17 (24.3) | 15 (20) | 12 (16.2) | 0.5 |
| Echocardiographic | ||||
| LV mass index (g/m2) | 218 ± 75.6 | 202 ± 74 | 251 ± 97.6 | 0.002 |
| LV volume index (ml/m2) | 63.3 ± 19.4 | 65.4 ± 20.6 | 68.4 ± 21.3 | 0.3 |
| LV ejection fraction (%) | 52.5 ± 8.9 | 52.2 ± 8.38 | 52.4 ± 7.59 | 1.0 |
| Dialysis | ||||
| Total weekly urea clearance | 1.74 ± 0.39 | 1.86 ± 0.40 | 1.83 ± 0.50 | 0.2 |
| PD urea clearance | 1.46 ± 0.34 | 1.55 ± 0.36 | 1.57 ± 0.35 | 0.1 |
| Renal urea clearance | 0.28 ± 0.38 | 0.31 ± 0.35 | 0.25 ± 0.49 | 0.4 |
| Total weekly CrCl (l/wk per 1.73 m2) | 57.8 ± 25.7 | 57.6 ± 19.5 | 53.5 ± 19.3 | 0.4 |
| PD CrCl (l/wk per 1.73 m2) | 38.5 ± 7.18 | 38.9 ± 8.51 | 41.7 ± 8.30 | 0.04 |
| Renal CrCl (l/wk per 1.73 m2) | 19.3 ± 27.1 | 18.7 ± 20.4 | 11.9 ± 21.3 | 0.1 |
| Normalized PCR (g/kg per day)b | 0.91 (0.81, 1.08) | 0.96 (0.87, 1.07) | 0.93 (0.79, 1.09) | 0.5 |
| % with RRF | 44 (62.9) | 55 (73.3) | 34 (45.9) | 0.04 |
| Residual GFR (ml/min per 1.73 m2)b | 0.91 (0.81, 1.08) | 0.96 (0.87, 1.07) | 0.93 (0.79, 1.09) | 0.01 |
| Biochemical | ||||
| Hemoglobin (g/dl) | 9.45 ± 1.90 | 9.20 ± 1.58 | 8.92 ± 1.62 | 0.2 |
| Serum albumin (g/dl) | 28.7 ± 5.10 | 29.1 ± 5.81 | 27.9 ± 4.46 | 0.4 |
| Plasma potassium (mmol/l) | 4.15 ± 0.60 | 4.06 ± 0.61 | 3.82 ± 0.59 | 0.004 |
| Plasma calcium (mmol/l) | 2.56 ± 0.23 | 2.52 ± 0.20 | 2.60 ± 0.24 | 0.08 |
| Plasma phosphate (mmol/l) | 1.73 ± 0.53 | 1.61 ± 0.39 | 1.69 ± 0.46 | 0.3 |
| Intact PTH (pmol/l)b | 42.8 (18.6, 62.8) | 33.6 (13.1, 61.2) | 50.7 (20.5, 53.9) | 0.6 |
| Total cholesterol (mmol/l) | 5.53 ± 1.22 | 5.30 ± 1.16 | 0.36 ± .1.21 | 0.5 |
| HDL-cholesterol (mmol/l) | 1.16 ± 0.35 | 1.25 ± 0.47 | 1.30 ± 0.43 | 0.2 |
| LDL-cholesterol (mmol/l) | 3.50 ± 0.96 | 3.17 ± 0.94 | 3.17 ± 1.03 | 0.08 |
| Triglyceride (mmol/l) | 2.13 ± 1.74 | 2.10 ± 1.46 | 2.03 ± 1.22 | 0.9 |
| hs-CRP (mg/l)b | 1.99 (0.78, 7.91) | 1.75 (0.80, 5.71) | 3.86 (1.24, 11.2) | 0.09 |
| Interleukin-6 (pg/ml)b | 8.05 (4.05, 18.15) | 9.30 (5.30, 15.90) | 10.2 (6.80, 19.20) | 0.1 |
| Fetuin-A (g/l) | 0.32 ± 0.06 | 0.31 ± 0.06 | 0.30 ± 0.08 | 0.6 |
| Troponin (μg/l)b | 0.03 (0.01, 0.14) | 0.03 (0.01, 0.12) | 0.08 (0.03, 0.17) | 0.01 |
| NT-pro-BNP (pg/ml)b | 4455 (1722, 18,249) | 5156 (2165, 13,395) | 7973 (1894, 28,291) | 0.3 |
| Dietary intake | ||||
| Fiber intake (g/d) | 6.94 ± 2.53 | 5.02 ± 1.76 | 3.05 ± 1.48 | <0.001 |
| Fiber intake density (g/d per 1000 kcal energy intake) | 5.27 ± 1.07 | 3.46 ± 0.38 | 2.14 ± 0.55 | <0.001 |
| Energy intake (kcal/kg per day) | 22.9 ± 7.46 | 26.5 ± 9.54 | 24.4 ± 8.83 | 0.05 |
| Protein intake (g/kg per day) | 1.07 ± 0.41 | 1.16 ± 0.49 | 1.08 ± 0.44 | 0.4 |
BP, blood pressure; CrCl, creatinine clearance; GFR, glomerular filtration rate; HDL, high-density lipoprotein; hs-CRP, high sensitive C-reactive protein; LDL, low-density lipoprotein; LV, left ventricular; NT-pro-BNP, N-terminal pro-brain natriuretic peptide; PCR, protein catabolic rate; PD, peritoneal dialysis; PTH, parathyroid hormone; RRF, residual renal function.
Fiber intake density defined as daily fiber intake adjusted per 1000 kcal energy intake.
Fiber intake density >4.10 g/d per 1000 kcal energy intake as upper tertile (reference group), 2.90 to 4.10 and <2.90 g/d per 1000 kcal energy intake as middle and lower tertiles, respectively.
Continuous data are expressed as mean ± SD unless specified otherwise.
Median (interquartile range).