Table 3.
Demographic and anthropometric characteristics and serum biochemistry of the metabolomics cohort, with stratification by stone status and body mass index
| Variable | Uric Acid Stone Formers, n=37 | Nonstone Formers | |
|---|---|---|---|
| BMI>30 kg/m2, n=13 | BMI<30 kg/m2, n=14 | ||
| Age, yr | 59 (50–65) | 55 (49–57) | 51 (47–57) |
| Sex (women/men) | 15/22 | 5/8 | 6/8 |
| Race/ethnicity | |||
| Asian | 1 (3%) | 0 (0%) | 0 (0%) |
| Black | 6 (16%) | 3 (23%) | 6 (43%) |
| Hispanic | 4 (11%) | 1 (8%) | 0 (0%) |
| White | 26 (70%) | 9 (69%) | 8 (57%) |
| BMI, kg/m2 | 37.5 (32.0–43.3) | 40.7 (32.2–47.0) | 24.5 (21.1–24.9)a,b |
| Sodium, mmol/L | 137 (137–139) | 137 (136–138) | 138 (137–138) |
| Potassium, mmol/L | 4.2 (4.1–4.5) | 4.3 (4.2–4.5) | 4.3 (4.2–4.5) |
| Chloride, mmol/L | 103 (102–105) | 103 (103–105) | 104 (103–105) |
| Bicarbonate, mmol/L | 25 (24–26) | 25 (24–26) | 28 (25–28) |
| pH | 7.38 (7.36–7.40) | 7.42 (7.40–7.43) | 7.38 (7.36–7.39) |
| Uric acid, mg/dl | 8.0 (7.2–8.9) | 7.0 (5.2–8.1) | 5.4 (5.0–6.3)a |
| BUN, mg/dl | 18 (15–20) | 14 (11–17) | 13 (12–14)a |
| Creatinine, mg/dl | 1.06 (0.81–1.41) | 0.77 (0.67–0.91)a | 0.84 (0.65–0.97) |
| Triglycerides, mg/dl | 206 (133–287) | 150 (98–172)a | 116 (84–137)a |
| Total cholesterol, mg/dl | 198 (181–236) | 183 (170–203) | 194 (179–208) |
| LDL cholesterol, mg/dl | 120 (92–153) | 110 (98–129) | 112 (85–124) |
| HDL cholesterol, mg/dl | 37 (30–45) | 41 (37–50)a | 58 (49–66)a,b |
| Free fatty acids, mmol/L | 0.47 (0.36–0.64) | 0.46 (0.37–0.52) | 0.37 (0.23–0.39)a,b |
| Fasting glucose, mg/dl | 102 (89–117) | 95 (92–100) | 84 (82–89)a,b |
Data are presented as median (interquartile range) or number of subjects (percentage). BMI, body mass index.
a
P<0.05 versus uric acid stone formers.
b
P<0.05 versus nonstone formers with BMI>30 kg/m2 by the Wilcoxon rank sum test.