Table 6.
Statistical analysis of reviewed studies for HD.
| Metabolite | Materials | Number of studies | SMD | 95%CI | I2(%) | P-value for heterogenicity |
|---|---|---|---|---|---|---|
| TRP | Blood (serum/plasma) | 5 | -0.90 | (-1.71, -0.10) | 91.0 | 0.000 |
| KYN | Blood (serum/plasma) | 3 | -0.37 | (-0.68, -0.06) | 28.5 | 0.247 |
| KYNA | Frontal cortex | 3 | 0.08 | (-0.88, 1.05) | 78.9 | 0.009 |
| 3-HK | Frontal cortex | 3 | 0.47 | (-0.41, 1.35) | 76.2 | 0.015 |
| 3-HANA | Blood (serum/plasma) | 3 | -0.32 | (-0.75, 0.12) | 57.4 | 0.095 |
TRP, tryptophan; KYN, kynurenine; KYNA, kynurenic acid; AA, anthranilic acid; 5HIAA, 5-hydroxyindoleacetic acid; 3-HK, 3-hydroxykynurenine; 3-HANA, 3-hydroxyanthranilic acid; CSF, Cerebrospinal fluid; SMD, standardized mean difference; CI, confidence interval.