06 November 2023 : Original article
Urinary Klotho Excretion: A Key Regulator of Sodium Homeostasis in Chronic Kidney Disease Stage 2-4
Po-Jui Chi12ABCDEF, Chung-Jen Lee3BCD, Shih-Yuan Hung
12CD, Jen-Pi Tsai45ABC, Hung-Hsiang Liou16ACDE*
DOI: 10.12659/MSMBR.942097
Med Sci Monit Basic Res 2023; 29:e942097
Table 1 Clinical and laboratory characteristics of patients with chronic kidney disease stratified by disease stage.
| Clinical and laboratory characteristics | CKD Stage | ||||
|---|---|---|---|---|---|
| All (n=53) | 2 (n=10) | 3 (n=34) | 4 (n=9) | P value | |
| Age (Years) | 71.1±10.5 | 67.8±9.1 | 70.4±11.5 | 77.3±3.5 | 0.113 |
| SBP (mmHg) | 134±18 | 141±21 | 133±17 | 133±20 | 0.478 |
| eGFR (mL/min/1.73 m) | 45.5±15.2 | 66.3±7.4 | 45.1±8.8 | 23.5±5.8 | <0.0001* |
| Uric acid (mg/dL) | 5.6 (4.4–6.3) | 6.1 (5.3–6.7) | 5.6 (4.3–6.3) | 5 (4.1–5.5) | 0.169 |
| Sodium (mEq/L) | 140 (138–141) | 140 (139–140.3) | 139 (137–141) | 140 (138–142) | 0.701 |
| Potassium (mEq/L) | 4.2±0.5 | 4±0.5 | 4.3±0.5 | 4.5±0.8 | 0.131 |
| Calcium (mg/dL) | 8.98 (8.7–9.14) | 8.98 (8.82–9.22) | 9.02 (8.66–9.18) | 8.94 (8.54–9.14) | 0.795 |
| Phosphorus (mg/dL) | 3.8±0.5 | 3.8±0.7 | 3.8±0.5 | 3.9±0.6 | 0.798 |
| Magnesium (mg/dL) | 2.1 (2.0–2.3) | 2.15 (1.9–2.3) | 2.1 (2.0–2.2) | 2.2 (2–2.4) | 0.586 |
| FENa (%) | 1.1 (0.5–1.5) | 0.4 (0.2–0.8) | 1.2 (0.7–1.5) | 1.3 (0.4–2.3) | 0.021* |
| FEK (%) | 12.9 (9.5–18.3) | 8.6 (6.5–10.6) | 13.2 (10.9–16.7) | 19.3 (12.8–34) | 0.002* |
| FECa (%) | 0.7 (0.4–1.3) | 0.8 (0.4–1.2) | 0.7 (0.4–1.4) | 0.6 (0.3–2) | 0.998 |
| FEPi (%) | 19.1±11.1 | 11±6.1 | 20.1±11 | 24.8±11 | 0.009* |
| FEMg (%) | 5.2 (3.3–7) | 2.2 (1.8–3.3) | 6.2 (3.9–7.1) | 6.4 (4.7–11.3) | 0.00027* |
| Hemoglobin (g/dL) | 13±2 | 14.3±1.3 | 13.1±1.9 | 11.1±1.9 | 0.001* |
| Urine protein to creatinine ratio(mg/g) | 387 (171–1363) | 346 (192–514) | 391 (164–1396) | 628 (212–2754) | 0.419 |
| 24-h urine protein (mg/d) | 226.8 (114.4–838.6) | 221.4 (159–432.7) | 181.2 (98.7–1227.1) | 355 (167.9–2699.5) | 0.595 |
| Intact PTH (pg/mL) | 38.2 (24.5–58.4) | 23.3 (15.8–40.3) | 35.4 (24.5–50.5) | 62.2 (47.8–79.8) | 0.001* |
| Klotho (pg/mL) | 408.8 (345.1–510.8) | 442.1 (368.3–539.8) | 393.1 (323.1–495.7) | 416.4 (376.3–545.6) | 0.201 |
| FEKlotho (%) | 0.016 (0.008–0.05) | 0.0101 (0.0029–0.0241) | 0.0168 (0.0096–0.0497) | 0.0368 (0.0049–0.0794) | 0.384 |
| C-terminal FGF23 (RU/mL) | 84.1 (56.4–108.6) | 54.3 (47.1–66.9) | 84.7 (58.2–108.3) | 110.1 (89.4–152.9) | 0.002* |
| Intact FGF23 (pg/mL) | 94.5 (74.6–115.1) | 77.9 (69.8–90.2) | 96.7 (79.8–117.1) | 110.5 (68.7–240.9) | 0.122 |
| 25-OH vitamin D (ng/mL) | 26.6 (21–32.4) | 30.3 (23.5–39) | 27.2 (22.5–34.4) | 19.3 (14–23.9) | 0.005* |
| Urine klotho to creatinine ratio | 4.28 (2.22–7.78) | 3.21 (1.66–8.57) | 4.46 (2.24–7.74) | 4.13 (1.75–13.58) | 0.881 |
| 24-h urine klotho(ng/d) | 8.5 (5.4–12.5) | 11 (6.5–14.3) | 8.7 (5.3–11) | 6.7 (5.1–12) | 0.523 |
| Male, n (%) | 36 (67.9) | 7 (70) | 25 (73.5) | 4 (44.4) | 0.248 |
| Diabetes mellitus, n (%) | 23 (43.4) | 4 (40) | 13 (38.2) | 6 (66.7) | 0.301 |
| Hypertension, n (%) | 43 (81.1) | 9 (90) | 28 (82.4) | 6 (66.7) | 0.411 |
| ACEi/ARB use, n (%) | 37 (69.8) | 8 (80) | 27 (73.5) | 4 (44.4) | 0.177 |
| CCB use, n (%) | 30 (56.6) | 6 (60) | 18 (52.9) | 6 (66.7) | 0.739 |
| Diuretics use, n (%) | 11 (20.8) | 3 (30) | 7 (20.6) | 1 (11.1) | 0.598 |
| Values for continuous variables are shown as mean±standard deviation and analyzed by one-way ANOVA test; variables not normally distributed are shown as median and 25–75 interquartile range, and are analyzed by the Kruskal-Wallis H test; values are presented as number (%) and analyzed by the Pearson’s chi-squared test. SBP – systolic blood pressure; eGFR – estimated glomerular filtration rate; FENa – fractional excretion of sodium; FEK – fractional excretion of potassium; FECa – fractional excretion of calcium; FEPi – fractional excretion of phosphate; FEMg – fractional excretion of magnesium; intact PTH – intact parathyroid hormone; FEKlotho – fractional excretion of Klotho; FGF23 – fibroblast growth factor; ACEi/ARB – angiotensin converting enzyme inhibitor/angiotensin II receptor blocker; CCB – calcium channel blocker. * Values of | |||||