Prostaglandin E2 and D2 metabolites and modelled exposure to air pollution in asthmatic children in whom a urine sample was obtained
| Mild asthma (BTS steps 1–2) | Moderate-to-severe asthma (BTS steps 3–5) | |
|---|---|---|
| N | 13 | 20 |
| Induced sputum eosinophils (%) | 0 (0 to 0) | 2** (0 to 10) |
| Alveolar macrophage carbon (μm2) | 0.37 (0.24 to 0.88) | 0.19** (0.11 to 0.26) |
| Mean annual PM2.5 (μg/m3) | 14.3 (14.1 to 14.6) | 14.3 (13.7 to 14.5) |
| Mean 7-day PM2.5 (μg/m3) | 15.3 (9.3 to 18.0) | 12.4 (10.1 to 21.0) |
| Mean 24 h PM2.5 (μg/m3) | 9.5 (7.9 to 10.1) | 11.5 (8.9 to 18.1) |
| Home address ≤50 m from a main road (n) | 2 | 4 |
| Urinary 13,14-dihydro-15-keto-tetranor-PGE2 (pg/mg creatinine) | 250 (119 to 450) | 505* (218 to 937) |
| Urinary 13,14-dihydro-15-keto-tetranor-PGD2 (pg/mg creatinine) | 225 (170 to 470) | 779** (259 to 1149) |
PM2.5, particulate matter <2.5 μm in aerodynamic diameter modelled at home address for 23/33 children. Sputum eosinophil differential is derived from 400 induced sputum leucocytes per child. AM carbon is derived from 50 AM per child. Urine samples were obtained from all children recruited via the Royal London Hospital. Data are described as median (IQR). *p<0.05 **p<0.01 versus mild asthmatics by Mann–Whitney test.
AM, airway macrophage; BTS, British Thoracic Society; PG, prostaglandin.