Table 1.
Anthropometric, clinical and metabolic characteristics of the patient group (patients with urolithiasis) and reference group
| Demographic, clinical and metabolic variables | Reference group (n = 517) | Urolithiasis group (n = 478) | p |
|---|---|---|---|
| Age (years) | 14.59 (10.64–16.60) | 14.79 (11.14–16.74) | NS |
| Gender, n (female/male) | 298/ 219 | 273/ 205 | NSa |
| BMI (kg/ m2) | 19.49 (17.01–22.02) | 19.36 (16.87–22.04) | NS |
| BMI Z-score | 0.08 (−0.56–0.79) | 0.03 (−0.65–0.83) | NS |
| Urine volume (mL/kg/24 h) | 19.70 (13.90–27.19) | 21.26 (14.81–29.17) | <0.05 |
| Creatinine (mg/dL) | 0.595 (0.47–0.71) | 0.60 (0.48–0.73) | NS |
| Uric acid (mg/dL) | 4.52 (3.83–5.47) | 4.53 (3.89–5.32) | NS |
| Urea (mg/dL) | 25 (21–29) | 25 (21–30) | NS |
| Cholesterol (mg/dL) | 151.5 (137–170) | 161 (138–186) | <0.01 |
| BRI (L−1) | 0.30 (0.12–0.80) | 0.96 (0.14–3.76) | <0.01 |
| Urine pH | 6.36 (6.03–6.70) | 6.33 (6.03–6.60) | NS |
| GFR (ml/min/1.73 m2) | 125.07 (110.49–143.52) | 123.60 (102.21–144.23) | NS |
| Oxalate/cr. (mmol/g cr.) | 0.28 (0.19–0.37) | 0.46 (0.23–0.69) | <0.01 |
| Citrate/cr. (mg/g cr.) | 585.10 (482.18–810) | 461.13 (277.64–702.18) | <0.01 |
| Ca/cr. (mmol/g cr.) | 2.87 (2.16–3.65) | 3.53 (2.07–5.86) | <0.01 |
| P/cr. (mmol/g cr.) | 20.36 (16.73–25.45) | 19.61 (15.47–26) | NS |
| Mg/cr. (mmol/g cr.) | 3.47 (2.98–4.11) | 3.32 (2.59–4.37) | NS |
| Uric acid/cr. | 0.43 (0.36–0.53) | 0.44 (0.36–0.57) | NS |
| Ca/citrate | 0.18 (0.13–0.24) | 0.32 (0.17–0.59) | <0.01 |
Data are presented as the median with the interquartile range [IQR; Q1 (lower quartile) and Q3 (upper quartile)] in parenthesis, unless otherwise indicated
BMI, Body mass index; GFR, glomerular filtration rate; BRI, Bonn Risk Index; cr., creatinine; Mg, magnesium; P, phosphorus; NS, not significant
aThe chi-square statistic was used