Table 4.
Targeted metabolomic results to amino acid analysis.
| Amino acid (µmol/L) | Total (n = 53) | No OSA (n = 16) | OSA (n = 37) | p value | CI dif. 95% | AUC (CI 95%) |
|---|---|---|---|---|---|---|
| Aspartic acid | 4.9 ± 1.0 | 4.7 ± 1.0 | 5.1 ± 1.5 | 0.467 | [−1.05; 0.40] | 0.564 (0.734–0.395) |
| Glutamic acid | 71.8 ± 20.7 | 83.5 ± 22.5 | 66.7 ± 24.5 | 0.023* | [2.70; 30.92] | 0.698 (0.847–0.549) |
| Alanine | 337.9 ± 50.4 | 333.8 ± 61.1 | 339.7 ± 71.2 | 0.723 | [−45.07; 33.25] | 0.532 (0.710–0.354) |
| Allo-isoleucine | 3.6 ± 1.2 | 3.9 ± 1.4 | 3.4 ± 1.4 | 0.378 | [−0.42; 1.30] | 0.578 (0.750–0.405) |
| Arginine | 61.8 ± 10.2 | 57.6 ± 10.6 | 63.6 ± 14.1 | 0.119 | [−13.15; 1.10] | 0.637 (0.803–0.471) |
| Asparagine | 36.0 ± 5.8 | 36.2 ± 4.8 | 36 ± 8.1 | 0.691 | [−3.34; 3.90] | 0.535 (0.693–0.378) |
| Citrulline | 29.7 ± 5.2 | 30.0 ± 5.3 | 29.6 ± 7.0 | 0.642 | [−3.17; 3.93] | 0.541 (0.703–0.380) |
| Phenylalanine | 45.8 ± 17.2 | 44.6 ± 16.5 | 46.3 ± 20.9 | 0.846 | [−12.61; 9.13] | 0.518 (0.678–0.358) |
| Glycine | 210.2 ± 34.7 | 208.4 ± 52.2 | 211.1 ± 41.4 | 0.574 | [−33.11; 27.71] | 0.550 (0.734–0.366) |
| Glutamine | 618.9 ± 73.1 | 585.2 ± 61.9 | 633.5 ± 93.7 | 0.067 | [−92.43; −4.32] | 0.660 (0.812–0.509) |
| Hydroxyproline | 11.2 ± 3.4 | 10.4 ± 4.0 | 11.6 ± 4.3 | 0.318 | [−3.71; 1.27] | 0.588 (0.762–0.414) |
| Histidine | 72.5 ± 6.4 | 69.8 ± 10.5 | 73.6 ± 6.8 | 0.215 | [−9.82; 2.10] | 0.609 (0.794–0.424) |
| Isoleucine | 85.1 ± 11.9 | 84.8 ± 15.4 | 85.3 ± 16.5 | 0.757 | [−10.17; 9.06] | 0.528 (0.710–0.346) |
| Leucine | 152.2 ± 18.9 | 152.9 ± 24.0 | 152.0 ± 24.0 | 0.946 | [−13.82; 15.64] | 0.507 (0.695–0.319) |
| Lysine | 178.1 ± 26.2 | 173.7 ± 34.2 | 180.0 ± 31.4 | 0.342 | [−26.80; 14.24] | 0.584 (0.757–0.411) |
| Methionine | 25.9 ± 2.3 | 25.1 ± 3.1 | 26.4 ± 2.9 | 0.337 | [−3.14; 0.61] | 0.584 (0.754–0.415) |
| Ornithine | 80.8 ± 15.2 | 81.5 ± 18.8 | 80.5 ± 19.5 | 0.794 | [−10.59; 12.69] | 0.524 (0.707–0.340) |
| Proline | 204.0 ± 15.2 | 200.1 ± 48.8 | 205.7 ± 39.0 | 0.611 | [−34.11; 22.86] | 0.546 (0.732–0.359) |
| Serine | 96.6 ± 12.9 | 100.6 ± 11.2 | 94.8 ± 18.2 | 0.104 | [−2.46; 14.05] | 0.643 (0.794–0.492) |
| Taurine | 28.6 ± 20.0 | 28.1 ± 25.4 | 28.8 ± 21.6 | 0.969 | [−15.71; 14.23] | 0.496 (0.679–0.312) |
| Tyrosine | 55.3 ± 14.0 | 52.4 ± 19.1 | 56.5 ± 17.1 | 0.584 | [−15.41; 7.35] | 0.549 (0.728–0.370) |
| Threonine | 92.8 ± 12.9 | 91.2 ± 12.1 | 93.6 ± 17.5 | 0.786 | [−10.82; 6.04] | 0.476 (0.639–0.312) |
| Thriptophan | 71.33 ± 6.8 | 71.5 ± 11.4 | 71.2 ± 8.4 | 0.713 | [−6.28; 6.89] | 0.533 (0.733–0.332) |
| Valine | 252.6 ± 27.5 | 252.8 ± 29.3 | 252.6 ± 37.6 | 0.698 | [−19.24; 19.63] | 0.465 (0.632–0.299) |
Averages are shown with standard deviation, p value, VIP score and AUC for each metabolite.
AUC: area under the curve; CI: confidence interval; OSA: obstructive sleep apnoea.