Table 2.
Characteristics of participant groups by amino acid profile cluster: significant differences in amino acid levels and symptom indices
| Pre-supplement large cohort (n = 151) | ||||
|---|---|---|---|---|
| Characteristic | Cluster 1 n = 48 |
Cluster 2 n = 33 |
Cluster 3 n = 70 |
p value |
| Mean Agea | 26.0 (1.2) | 37.8 (2.3) | 31.9 (1.6) | C1 < C2 = C3 p < 0.001 |
| Mean BMIa | 24.8 (0.4) | 24.2 (0.7) | 25.4 (0.4) | ns |
| Proportion Males (number)a | 75% (36) | 30.3% (10) | 75.7% (53) | C2 < C1 = C3 p < 0.001 |
| Caucasian (%)a | 95.1% | 100% | 93.8% | ns |
| Urine Amino Acids | ||||
| Total amino acids μmole/L | 6,609 (495) | 4,339 (462) | 4,425 (306) | C1 > C2 = C3 p < 0.01‡ |
| Histidine | 2,152 (185) | 599 (76) | 886 (74) | C1 > C2 = C3 p < 0.0001 |
| Glycine | 1,077 (86) | 1,412 (157) | 861 (68) | C2 > C3 p < 0.001 |
| Glutamine | 626 (63) | 443 (46) | 480 (29) | C1 > C2 = C3 p < 0.05 |
| Serine | 411 (49) | 320 (34) | 279 (16) | C1 > C3 p < 0.05 |
| Alanine | 313 (29) | 232 (25) | 236 (18) | C1 > C3 p < 0.05 |
| Tyrosine | 129 (13) | 57 (8) | 77 (5) | C1 > C2 = C3 p < 0.0001 |
| Branched chain amino acids | 106 (7) | 62 (7) | 84 (6) | C1 > C2 = C3 p < 0.001 |
| Proline | 5.0 (1.9) | 9.1 (2.0) | 10.7 (1.5) | ns |
| Symptom Indices | ||||
| Chalder total fatigue | 12.8 (0.7) | 16.0 (1.0) | 13.4 (0.8) | C2 > C1 p < 0.05 |
| Chalder mental fatigue | 4.5 (0.3) | 5.9 (0.4) | 4.6 (0.3) | C2 > C1 = C3 p < 0.05 |
| General fatigue index | 3.2 (1.0) | 11.2 (1.6) | 8.3 (1.1) | C2 > C1 p < 0.05 |
| Pain index | 5.1 (0.8) | 8.1 (1.3) | 5.3 (0.7) | ns |
| Gastrointestinal index | 1.7 (0.7) | 3.8 (1.0) | 2.0 (0.4) | ns |
| Sleep index | 8.2 (1.0) | 14.0 (1.9) | 11.5 (1.2) | C2 > C1 p < 0.05 |
| Vitality index | 6.5 (1.2) | 9.1 (1.3) | 5.5 (0.8) | ns |
Statistical tests: ANOVA, Tukey’s HSD for unequal sample sizes, *Chi square; mean (SEM)