Table 1.
Clinical characteristics and plasma concentrations of microbial metabolites in participants.
| Healthy controls (N = 250) | PD patients (N = 250) | P-value | |
|---|---|---|---|
| Age (years) | 67.4 ± 7.5 | 67.4 ± 7.7 | 0.95 |
| Sex (male), n (%) | 165 (66.0) | 164 (65.6) | 0.93 |
| BMI | 22.6 ± 1.4 | 22.6 ± 1.5 | 0.99 |
| Constipation, n (%) | 103 (41.2) | 130 (52.0) | 0.01* |
| Creatinine (mg/dL) | 0.9 ± 0.3 | 0.9 ± 0.2 | 0.96 |
| Disease duration (years) | N.A. | 7.4 ± 2.4 | |
| Hoehn-and-Yahr stage | N.A. | 3.2 ± 0.9 | |
| Early-stage, n (%) | N.A. | 46 (18.4%) | |
| Advanced-stage, n (%) | N.A. | 204 (81.6%) | |
| MDS-UPDRS part III | N.A. | 35.0 ± 9.9 | |
| MMSE | 28.7 ± 1.8 | 26.5 ± 2.7 | <0.01** |
| LEDD | N.A. | 649.2 ± 206.0 | |
| Plasma metabolites (ng/mL) | |||
| Phenylalanine (PHE) | 9733.7 ± 1868.1 | 9674.9 ± 2252.9 | 0.50 |
| Phenylacetic acid (PAA) | 81.9 ± 106.1 | 113.7 ± 82.9 | <0.001*** |
| Phenylacetylglutamine (PAGln) | 849.1 ± 2778.0 | 1024.3 ± 1025.6 | <0.001*** |
| Phenyllactic acid (PLA) | 26.7 ± 15.1 | 30.3 ± 18.7 | 0.02* |
| Phenylpropionic acid (PPA) | 28.8 ± 40.6 | 61.5 ± 122.7 | <0.001*** |
| P-cresol sulfate (Pcs) | 2110.7 ± 2603.1 | 3265.1 ± 2899.3 | <0.001*** |
| P-cresol glucuronide (Pcg) | 25.2 ± 101.8 | 41.5 ± 61.5 | <0.001*** |
| Indoxyl sulfate (IS) | 1059.8 ± 2838.7 | 1132.2 ± 1380.6 | <0.001*** |
| Medical co-morbidity, n (%) | |||
| Diabetes mellitus | 61 (24.4) | 49 (19.6) | 0.19 |
| Hypertension | 68 (27.2) | 53 (21.2) | 0.12 |
| History of cardiovascular disease | 40 (16.0) | 31 (12.4) | 0.25 |
| History of stroke | 32 (12.8) | 23 (9.2) | 0.19 |
Variables are expressed as mean ± standard deviation or number (percentage).
BMI body mass index, IS indoxyl sulfate, LEDD levodopa equivalent daily dose, MDS-UPDRS Movement Disorder Society Unified PD Rating Scale, MMSE Mini-Mental State Examination, N.A. not available, Pcg p-Cresol glucuronide, Pcs p-Cresol sulfate, PAA phenylacetic acid, PAGln phenylacetylglutamine, PHE phenylalanine, PLA phenyllactic acid, PPA phenylpropionic acid. *P < 0.05; **P < 0.01; ***P < 0.001.