Table 4.
Changes in renal function, neuropsychological performance, and amino acid and kynurenine metabolism during the intervention.
| Group | Baseline | 24 Weeks | p for Time | Changes | p for Groups | |
|---|---|---|---|---|---|---|
| eGFR (mL/min/1.73 m2) | B | 69 ± 16 | 71 ± 14 | 0.469 | 0 ± 6 | 0.241 |
| S | 66 ± 16 | 68 ± 17 | 0.602 | 2 ± 7 | ||
| Urinary albumin excretion (mg/day) * | B | 23 (5–94) | 11 (4–52) | 0.258 | −3 (−23–1) | 0.047 |
| S | 13 (6–51) | 12 (4–53) | 0.386 | −1 (−2–23) | ||
| MMSE (points) | B | 28 (27–30) | 29 (26–30) | 0.667 | 0 (−1–1) | 0.086 |
| S | 29 (27–30) | 30 (28–30) | 0.055 | 1 (0–1) | ||
| QIDS (points) | B | 6 (3–8) | 4 (2–7) | 0.019 | −2 (−4–1) | 0.400 |
| S | 4 (2–6) | 3 (2–4) | 0.149 | −1 (−3–1) | ||
| SAS (points) | B | 11 (4–16) | 10 (4–16) | 0.599 | −1 (−3–2) | 0.298 |
| S | 13 (4–15) | 12 (8–16) | 0.461 | 1 (−2–4) | ||
| Total amino acids (μmol/L) | B | 3004 ± 261 | 3149 ± 198 | 0.010 | 145 ± 226 | 0.382 |
| S | 2884 ± 267 | 2960 ± 202 | 0.232 | 76 ± 235 | ||
| Branched-chain amino acids (μmol/L) | B | 407 ± 75 | 446 ± 68 | 0.015 | 39 ± 66 | 0.381 |
| S | 391 ± 62 | 412 ± 76 | 0.186 | 21 ± 57 | ||
| Essential amino acids (μmol/L) | B | 840 ± 111 | 891 ± 87 | 0.034 | 51 ± 99 | 0.629 |
| S | 812 ± 91 | 847 ± 99 | 0.175 | 35 ± 94 | ||
| Non-essential amino acids (μmol/L) | B | 2154 ± 189 | 2250 ± 155 | 0.021 | 96 ± 171 | 0.348 |
| S | 2063 ± 200 | 2104 ± 127 | 0.365 | 41 ± 169 | ||
| Large neutral amino acids (μmol/L) | B | 783 ± 105 | 836 ± 82 | 0.025 | 53 ± 97 | 0.527 |
| S | 764 ± 84 | 796 ± 96 | 0.170 | 33 ± 87 | ||
| Leucine (μmol/L) | B | 124 ± 26 | 135 ± 23 | 0.014 | 12 ± 19 | 0.224 |
| S | 121 ± 23 | 125 ± 24 | 0.601 | 3 ± 22 | ||
| Isoleucine (μmol/L) | B | 74 ± 15 | 78 ± 16 | 0.184 | 4 ± 13 | 0.650 |
| S | 71 ± 14 | 77 ± 18 | 0.075 | 6 ± 12 | ||
| Valine (μmol/L) | B | 209 ± 36 | 233 ± 32 | 0.012 | 24 ± 38 | 0.303 |
| S | 198 ± 28 | 210 ± 36 | 0.109 | 12 ± 26 | ||
| Tryptophan (μmol/L) | B | 50 ± 8 | 55 ± 9 | 0.004 | 5 ± 6 | 0.254 |
| S | 50 ± 10 | 52 ± 7 | 0.329 | 2 ± 7 | ||
| Lysine (μmol/L) * | B | 115 (106–126) | 121 (109–129) | 0.198 | 2 (−7–12) | 0.854 |
| S | 107 (93–120) | 112 (101–124) | 0.225 | 6 (−7–22) | ||
| Methionine (μmol/L) | B | 25 ± 4 | 27 ± 4 | 0.080 | 2 ± 4 | 0.393 |
| S | 23 ± 3 | 24 ± 4 | 0.696 | 0 ± 5 | ||
| Phenylalanine (μmol/L) | B | 58 ± 10 | 61 ± 9 | 0.054 | 3 ± 7 | 0.499 |
| S | 55 ± 10 | 56 ± 10 | 0.622 | 1 ± 10 | ||
| Threonine (μmol/L) * | B | 127 (119–139) | 122 (113–135) | 0.594 | −2 (−18–10) | 0.366 |
| S | 130 (116–148) | 142 (118–154) | 0.264 | 6 (−10–17) | ||
| Histidine (μmol/L) | B | 53 ± 9 | 53 ± 7 | 0.919 | 0 ± 7 | 0.485 |
| S | 51 ± 7 | 52 ± 7 | 0.435 | 2 ± 7 | ||
| Tyrosine (μmol/L) | B | 61 ± 10 | 66 ± 13 | 0.028 | 5 ± 9 | 0.297 |
| S | 60 ± 9 | 62 ± 9 | 0.340 | 2 ± 7 | ||
| Aspartic acid (μmol/L) | B | 37 ± 7 | 38 ± 7 | 0.645 | 1 ± 10 | 0.757 |
| S | 36 ± 5 | 36 ± 7 | 0.979 | 0 ± 8 | ||
| Asparagine (μmol/L) | B | 73 ± 7 | 77 ± 9 | 0.042 | 4 ± 8 | 0.766 |
| S | 71 ± 8 | 74 ± 9 | 0.212 | 3 ± 9 | ||
| Serine (μmol/L) | B | 195 ± 35 | 203 ± 35 | 0.183 | 7 ± 23 | 0.457 |
| S | 191 ± 21 | 192 ± 19 | 0.864 | 1 ± 24 | ||
| Glutamic acid (μmol/L) | B | 53 ± 14 | 54 ± 11 | 0.723 | 1 ± 15 | 0.225 |
| S | 53 ± 15 | 47 ± 17 | 0.217 | −5 ± 16 | ||
| Glutamine (μmol/L) | B | 1062 ± 110 | 1115 ± 98 | 0.022 | 53 ± 95 | 0.534 |
| S | 986 ± 122 | 1018 ± 86 | 0.250 | 32 ± 104 | ||
| Proline (μmol/L) * | B | 82 (73–93) | 87 (78–105) | 0.144 | 2 (−7–11) | 0.068 |
| S | 88 (75–104) | 78 (74–93) | 0.126 | −4 (−13–4) | ||
| Glycine (μmol/L) | B | 209 ± 28 | 207 ± 29 | 0.761 | −2 ± 29 | 0.398 |
| S | 203 ± 33 | 209 ± 33 | 0.384 | 6 ± 26 | ||
| Alanine (μmol/L) | B | 300 ± 47 | 317 ± 43 | 0.085 | 17 ± 42 | 0.249 |
| S | 295 ± 62 | 297 ± 67 | 0.766 | 2 ± 29 | ||
| Arginine (μmol/L) | B | 78 ± 16 | 82 ± 18 | 0.141 | 4 ± 13 | 0.832 |
| S | 79 ± 18 | 82 ± 16 | 0.267 | 3 ± 12 | ||
| Cystine (μmol/L) * | B | 9 (6–11) | 6 (4–9) | 0.137 | −3 (−6–2) | 0.772 |
| S | 8 (4–12) | 7 (5–12) | 0.872 | 3 (−4–7) | ||
| Kynurenine (μmol/L) | B | 4.4 ± 0.9 | 4.5 ± 0.8 | 0.925 | 0.0 ± 1.0 | 0.521 |
| S | 4.2 ± 0.9 | 4.4 ± 0.9 | 0.256 | 0.2 ± 0.7 | ||
| Kynurenic acid (μmol/L) * | B | 0.04 (0.03–0.04) | 0.03 (0.03–0.04) | 0.449 | 0.00 (−0.01–0.01) | 0.218 |
| S | 0.04 (0.03–0.05) | 0.04 (0.03–0.06) | 0.587 | 0.01 (−0.01–0.01) | ||
| Tryptophan to large neutral amino acid ratio * | B | 0.06 (0.06–0.07) | 0.07 (0.06–0.07) | 0.313 | 0.00 (0.00–0.01) | 0.641 |
| S | 0.07 (0.06–0.07) | 0.07 (0.06–0.07) | 0.955 | 0.00 (0.00–0.00) | ||
| Tryptophan to branched-chain amino acids ratio * | B | 0.12 (0.11–0.14) | 0.13 (0.11–0.14) | 0.823 | 0.00 (−0.01–0.01) | 0.783 |
| S | 0.13 (0.12–0.15) | 0.12 (0.12–0.15) | 0.865 | 0.00 (0.01–0.01) | ||
| Kynurenine to tryptophan ratio * | B | 0.09 (0.07–0.10) | 0.08 (0.07–0.09) | 0.117 | 0.00 (−0.02–0.01) | 0.156 |
| S | 0.08 (0.07–0.09) | 0.08 (0.07–0.09) | 0.955 | 0.00 (−0.01–0.01) |
Data are mean ± SD or median (interquartile range). * log-transformed variables are used for the analyses. B, branched-chain amino acids (BCAA) group; eGFR, estimated glomerular filtration rate; HDL-C, high-density lipoprotein cholesterol; HOMA-IR, homeostasis model assessment of insulin resistance; LDL-C, low-density lipoprotein cholesterol; MMSE, Mini Mental State Examination; QIDS, Quick Inventory of Depressive Symptomatology; S, Soy protein group; SAS, Starkstein Apathy Scale.