Table 2.
Summary of global metabolomic analysis: frequency of significant fold differences between plasma concentrations in cases (who subsequently progressed to ESRD) and controls (did not progress) according to type of metabolite and its recognition as a uremic solute
| Biochemical class: | All common metabolites | Uremic solutes | ||||
|---|---|---|---|---|---|---|
| Total | Associated with ESRD* | Total | Associated with ESRD* | |||
| n | n | (%) | n | n | (%) | |
| Lipids: | ||||||
| Common metabolites† | 126 | 4 | (3%) | 0 | 0 | (0%) |
| Stable metabolites ‡ | 51 | 2 | (4%) | 0 | 0 | (0%) |
| Amino acid and derivatives: | ||||||
| Common metabolites† | 67 | 25 | (37%) | 10 | 3 | (30%) |
| Stable metabolites ‡ | 35 | 14 | (40%) | 6 | 2 | (33%) |
| Carbohydrates: | ||||||
| Common metabolites† | 20 | 9 | (45%) | 6 | 6 | (100%) |
| Stable metabolites ‡ | 14 | 6 | (42%) | 5 | 5 | (100%) |
| Nucleotides: | ||||||
| Common metabolites† | 12 | 7 | (58%) | 10 | 7 | (70%) |
| Stable metabolites ‡ | 7 | 4 | (57%) | 5 | 4 | (80%) |
| Other metabolites: | ||||||
| Common metabolites† | 37 | 4 | (11%) | 1 | 0 | (0%) |
| Stable metabolites ‡ | 12 | 2 | (16%) | 0 | 0 | (0%) |
| TOTAL: | ||||||
| Common metabolites† | 262 | 49 | (19%) | 27 | 16 | (55%) |
| Stable metabolites over time ‡ | 119 | 28 | (23%) | 18 | 12 | (67%) |
*
Values of fold difference were significantly different from 1.0 at a q-value <0.05. See also Figure 1 A & B.
†
Detectable in plasma of ≥80% of patients
‡
Common and stable over time, i.e. Spearman correlation coefficient ≥0.4 between measurements taken 1-2 years apart from the same individual. Out of 29 stable metabolites associated with ESRD, five were not examined further.