Table 3.
Effects of salt loading on measures of kidney function
| Placebo | Salt | P Value | |
|---|---|---|---|
| Urine creatinine excretion, mg/day | 1,240 ± 398 | 1,598 ± 231 | <0.001* |
| Serum creatinine, mg/dL | 0.8 ± 0.1 | 0.8 ± 0.1 | 0.552 |
| Unadjusted creatinine clearance, mL/min | 110.5 ± 32.9 | 145.4 ± 23.9 | <0.001* |
| High GFR | 6/18 (33%) | 12/18 (67%) | 0.046* |
| Adjusted creatinine clearance, per 1.73 m2 | 105.6 ± 30.8 | 137.0 ± 23.7 | <0.001* |
| High GFR | 6/18 (33%) | 10/18 (56%) | 0.180 |
| Urinary cystatin C excretion, mg/day | 0.15 ± 0.06 | 0.22 ± 0.09 | 0.015* |
| Urea excretion, g/day | 18.8 ± 13.4 | 19.9 ± 13.7 | 0.543 |
| Plasma angiotensin II, pg/mL | 20.9 ± 4.3 | 18.2 ± 3.1 | 0.006* |
| Fractional excretion of Na+, % | 0.62 ± 0.39 | 0.98 ± 0.29 | <0.001* |
Data are presented as means ± SD. GFR, glomerular filtration rate. *Statistical significance. t tests or Wilcoxon tests were used for continuous variables.