Table 2.
Plasma Metabolites Cross-sectionally Associated with Dietary Intake of Protein-Rich foods and Prospectively Associated with CKD Progression in the CKiD Study
| Cross-sectional analysis with dietary intake of protein† | Prospective analysis with CKD progression‡ | |||||
|---|---|---|---|---|---|---|
| Compound | Superpathway | Subpathway | β (SE) | FDR p-value | HR (95% CI) | FDR p-value |
| Metabolites Significantly Associated with Dietary Intake of Animal Protein (n=1) | ||||||
| sphingomyelin (d18:1/14:0, d16:1/16:0)* | Lipid | Sphingomyelins | 0.0039 (0.0009) | 0.008 | 2.49 (1.46, 4.26) | 0.02 |
| Metabolites Significantly Associated with Dietary Intake of Dairy (n=7) | ||||||
| carotene diol (2) | Cofactors and Vitamins | Vitamin A Metabolism | −0.0271 (0.0064) | 0.003 | 1.50 (1.11, 2.02) | 0.048 |
| myristoyl dihydrosphingomyelin (d18:0/14:0)* | Lipid | Dihydrosphingomyelins | 0.0236 (0.0050) | 0.0006 | 2.10 (1.32, 3.36) | 0.02 |
| sphingomyelin (d18:1/14:0, d16:1/16:0)* | Lipid | Sphingomyelins | 0.0235 (0.0039) | 2.55 × 10−6 | 2.49 (1.46, 4.26) | 0.02 |
| sphingomyelin (d17:1/16:0, d18:1/15:0, d16:1/17:0)* | Lipid | Sphingomyelins | 0.0205 (0.0038) | 3.73 × 10−5 | 2.45 (1.40, 4.29) | 0.02 |
| phenylacetylglycine | Peptide | Acetylated Peptides | 0.0742 (0.0164) | 0.0012 | 1.22 (1.06, 1.40) | 0.04 |
| urate | Nucleotide | Purine Metabolism, (Hypo)Xanthine/Inosine containing | −0.0104 (0.0031) | 0.0396 | 3.25 (1.44, 7.31) | 0.04 |
| homostachydrine* | Xenobiotics | Food Component/Plant | 0.0334 (0.0097) | 0.0374 | 1.55 (1.24, 1.93) | 0.006 |
| Metabolites Significantly Associated with Dietary Intake of Red and Processed Meat (n=2) | ||||||
| 1-(1-enyl-palmitoyl)-2-oleoyl-GPE (P-16:0/18:1)* | Lipid | Plasmalogen | 0.0130 (0.0034) | 0.0135 | 1.88 (1.19, 2.99) | 0.0470 |
| 3-ureidopropionate | Nucleotide | Pyrimidine Metabolism, Uracil containing | −0.0124 (0.0037) | 0.0427 | 0.52 (0.35, 0.77) | 0.02 |
| Metabolites Significantly Associated with Dietary Intake of Nuts and Beans (n=1) | ||||||
| tryptophan betaine | Amino Acid | Tryptophan Metabolism | 0.1770 (0.0211) | 5.58 × 10−13 | 1.24 (1.10, 1.39) | 0.008 |
For the cross-sectional analysis of dietary intake of protein and metabolites, models were adjusted for age, sex, race, body mass index Z-score, glomerular or non-glomerular diagnosis, estimated glomerular filtration rate (calculated using the CKiD under 25 equation), total energy intake, and dietary intake of fruit, whole grains, and refined grains. The model for each of the six protein-rich food was further adjusted for the other five food groups.
For the prospective analysis of metabolites and CKD progression, models were adjusted for age, sex, race, body mass index Z-score, glomerular or non-glomerular diagnosis, estimated glomerular filtration rate (calculated using the CKiD under 25 equation), log2-transformed protein-to-creatinine ratio, anemia, hypertension, and serum albumin.
Asterisk indicates metabolites not officially confirmed (tier 2 identification).
Abbreviations: CKD, chronic kidney disease; CKiD, Chronic Kidney Disease in Children study; CI, confidence interval; FDR, false discovery rate; GPE, glycerophosphoethanolamine; HR, hazard ratio; SE, standard error.