Three gut bacterial community clusters in the asthmatic group differ in several clinical and inflammatory features (median values unless otherwise noted)
| Feature | Cluster 1 (n=8) | Cluster 2 (n=3) | Cluster 3 (n=13) | P values |
| Age | 39 | 27 | 44 | |
| FEV1/FVC | 0.81 | 0.64 | 0.66 | 0.03 |
| FEV1 (L) | 2.82 | 3.9 | 2.6 | 0.03 |
| FEV1 (%predicted) | 99.5 | 86% | 79% | |
| FVC (L) | 3.4 | 5.35 | 4.22 | 0.04 |
| PC20 (mg/mL) | 0.76 | 0.37 | 0.38 | |
| PD20 (µg) | 209.5 | 97 | 98 | |
| Bronchodilator reversibility (L) | 0.16 | 0.28 | 0.3 | |
| Bronchodilator reversibility (%) | 6 | 7 | 11.5 | |
| ACQ-7 | 0.7 | 1.4 | 0.9 | |
| ACT | 20.5 | 18 | 22 | |
| BMI (kg/m2) | 35.2 | 26.6 | 25 | |
| Obese (BMI≥30) (%) | 63 | 33 | 15 | 0.08 |
| Adult-onset asthma | 3 | 0 | 5 | |
| Inhaled steroid use | 4 (50%) | 1 (33%) | 9 (69%) | |
| Total caloric intake (daily) | 1876 | 1579 | 1878 | |
| Total carbohydrate (g)(daily) | 261 | 160 | 213 | |
| Total protein (g) (daily) | 65 | 55 | 76 | |
| Total fat (g) (daily) | 65 | 61 | 78 | |
| Fruit total (daily equivalent or eq.) | 2.1 cup eq | 0.9 cup eq | 1.4 cup eq | 0.03 |
| Shannon index | 3.21 | 2.86 | 3.71 | 0.001 |
| Blood sRAGE (pg/mL) | 84.9 | 125.9 | 94.7 | 0.09 |
| Sputum eosinophils (%) | 0 | 1.2 | 0.4 | |
| Sputum IL-8 (pg/mL) | 661.2 | 2596 | 1378 | 0.09 |
| Sputum IL1-β (pg/mL) | 11.0 (0.6–314.6) | 99.3 (82–138) | 31.3 (0–2252) | 0.10 |
| Sputum TNF-α (pg/mL) | 3.1 (0–45) | 32.8 (10–35) | 129.6 (0–426) | |
| Top taxa | Blautia (OTU0026) 8.8% | Prevotella (OTU0017) 36.9% | Roseburia (OTU0024) 6.0% | |
| Mean relative abundance (%) | Bacteroides (OTU0015) 8.6% | Prevotellaceae (unclassified) (OTU0088) 7.3% | Bacteroides (OTU0015) 5.56% | |
| Bifidobacterium (OTU0028) 6.3% | Roseburia (OTU0024) 3.3% | Faecalibacterium (OTU0022) 5.5% | ||
| Prevotella (OTU0017) 5.6% | Faecalibacterium (OTU0022) 3.2% | Ruminococcus (OTU0034) 4.3% | ||
| Megasphaera (OTU0048) 3.8% | Prevotella (OTU0162) 2.7% | Blautia (OTU0026) 3.6% | ||
| Anae rostipes (OTU0037) 3.0% | Bifidobacterium (OTU0028) 2.1% | Anaerostipes (OTU0037) 3.6% |
Only p values ≤0.10 shown, otherwise not significant between clusters.
ACQ-7, Asthma Control Questionnaire-7; ACT, Asthma Control Test;BMI, body mass index; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; IL, interleukin; OTU, operational taxonomic unit; PC20 or PD20, provocative concentration or dose resulting in 20% decline in FEV1; TNF, tumour necrosis factor; sRAGE, soluble receptor for advanced glycation end-products.