TABLE 6.
Markers of protein-energy status, electrolytes, and bone metabolic status at study days 1 and 21
| nHMF | cHMF | ||||||||
| Variable | n | Median | IQR | Geometric mean | n | Median | IQR | Geometric mean | P* |
| Serum creatinine, μmol/L | |||||||||
| D1 | 69 | 44.0 | 36.2–48.0 | 41.5 | 70 | 44.1 | 38.0–51.8 | 43.5 | 0.303 |
| D21 | 63 | 28.0 | 23.5–32.0 | 26.7 | 65 | 30.0 | 25.0–35.0 | 29.5 | 0.001 |
| BUN, mmol/L | |||||||||
| D1 | 70 | 3.10 | 1.70–4.56 | 2.89 | 71 | 2.50 | 1.65–4.67 | 2.73 | 0.585 |
| D21 | 63 | 3.90 | 3.05–4.65 | 3.89 | 64 | 2.15 | 1.50–2.63 | 2.15 | <0.001 |
| Serum prealbumin, mg/L | |||||||||
| D1 | 51 | 100 | 80–120 | 96.8 | 46 | 90 | 80–100 | 87.8 | 0.073 |
| D21 | 46 | 116 | 91.3–140 | 113.8 | 41 | 100 | 90–120 | 98.1 | 0.015 |
| Urinary urea†, mmol/10 mg creatinine | |||||||||
| D1 | 47 | 2.7 | 2.0–4.7 | 2.8 | 53 | 2.5 | 1.9–3.3 | 2.5 | 0.302 |
| D21 | 42 | 5.8 | 4.6–6.8 | 5.1 | 40 | 2.8 | 2.0–3.3 | 2.7 | <0.001 |
| Serum calcium, mmol/L | |||||||||
| D1 | 50 | 2.44 | 2.31–2.53 | 2.41 | 54 | 2.47 | 2.38–2.56 | 2.44 | 0.445 |
| D21 | 50 | 2.47 | 2.40–2.54 | 2.46 | 48 | 2.43 | 2.34–2.53 | 2.43 | 0.019 |
| Serum phosphorus, mmol/L | |||||||||
| D1 | 68 | 1.99 | 1.85–2.22 | 1.96 | 71 | 1.94 | 1.76–2.25 | 1.94 | 0.816 |
| D21 | 62 | 2.10 | 1.93–2.23 | 2.05 | 64 | 2.12 | 1.93–2.26 | 2.08 | 0.681 |
| Alkaline phosphatase, U/L | |||||||||
| D1 | 67 | 353.0 | 298.5–459.5 | 377.9 | 63 | 333.0 | 250.0–438.5 | 343.8 | 0.208 |
| D21 | 62 | 320.5 | 273.3–405.5 | 337.5 | 62 | 270.5 | 233.0–354.3 | 297.5 | 0.010 |
| Urinary calcium †, mmol/10 mg creatinine | |||||||||
| D1 | 60 | 0.11 | 0.07–0.19 | 0.12 | 69 | 0.14 | 0.09–0.20 | 0.12 | 0.985 |
| D21 | 55 | 0.14 | 0.09–0.23 | 0.15 | 54 | 0.21 | 0.13–0.32 | 0.19 | 0.011 |
| Urinary phosphorus†, mmol/10 mg creatinine | |||||||||
| D1 | 59 | 0.41 | 0.12–0.66 | 0.22 | 65 | 0.34 | 0.14–0.65 | 0.23 | 0.867 |
| D21 | 52 | 0.68 | 0.44–1.10 | 0.53 | 52 | 0.71 | 0.40–0.92 | 0.58 | 0.896 |
| Urinary calcium:phosphorus molar ratio | |||||||||
| D1 | 59 | 0.39 | 0.15–0.90 | 0.50 | 64 | 0.41 | 0.16–1.34 | 0.47 | 0.824 |
| D21 | 53 | 0.22 | 0.12–0.48 | 0.28 | 53 | 0.31 | 0.19–0.60 | 0.34 | 0.054 |
| Serum sodium, mmol/L | |||||||||
| D1 | 71 | 138.0 | 137.0–140.0 | 138.6 | 72 | 138.6 | 136.6–140.0 | 138.5 | 0.891 |
| D21 | 65 | 138.0 | 136.4–140.0 | 138.0 | 64 | 138.0 | 137.0–139.9 | 138.3 | 0.449 |
| Serum potassium, mmol/L | |||||||||
| D1 | 71 | 4.73 | 4.30–5.32 | 4.83 | 72 | 4.77 | 4.40–5.10 | 4.78 | 0.685 |
| D21 | 64 | 4.74 | 4.29–5.10 | 4.72 | 64 | 4.51 | 4.14–4.88 | 4.54 | 0.091 |
| Serum chloride, mmol/L | |||||||||
| D1 | 71 | 106.0 | 104.0–109.0 | 106.1 | 72 | 105.0 | 102.8–108.0 | 105.2 | 0.148 |
| D21 | 63 | 105.0 | 103.0–107.0 | 104.6 | 62 | 105.0 | 104.0–107.0 | 105.3 | 0.111 |
BUN = blood urea nitrogen; cHMF = control human milk fortifier; D1 = study day 1; D21 = study day 21; IQR = interquartile range; nHMF = new human milk fortifier.
*D1 geometric mean values were log-transformed and analyzed using t test; D21 geometric mean values were log-transformed and analyzed using analysis of covariance (adjusting for the relevant biochemical parameter at D1, sex, and center).
†Corrected for urinary creatinine excretion of 10 mg/kg body weight/day.