Table 1 Frequency of chronic bronchitis symptoms and average of air pollutants (outdoor home NO2 and city average PM2.5 and S) by centre.
| Centre* | n | Prevalence at ECRHS‐I | Prevalence at ECRHS‐II | New onset† at ECRHS‐II | n | NO2 (μg/m3) | Range | PM2.5 (μg/m3) | S (ng/m3) | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chronic phlegm | Productive chronic cough | Chronic phlegm | Productive chronic cough | Chronic phlegm | Productive chronic cough | |||||||
| Erfurt (C) | 287 | 2.75 | 1.94 | 3.48 | 3.07 | 1.89 | 1.99 | 0 | – | 16.3 | 1144.3 | |
| Turin (S) | 123 | 7.79 | 2.47 | 3.25 | 0.85 | 3.57 | 0.86 | 72 | 70.81 | (35–136) | 44.9 | 1827.4 |
| Antwerp City (C) | 299 | 9.61 | 6.07 | 7.82 | 4.25 | 4.28 | 3.25 | 52 | 47.79 | (28–78) | 24.1 | 1464.7 |
| Basel (C) | 459 | 3.43 | 2.03 | 3.28 | 2.06 | 2.48 | 1.42 | 89 | 34.62 | (18–69) | 17.4 | 1038.9 |
| Norwich (C) | 257 | 3.85 | 1.51 | 5.49 | 2.55 | 3.51 | 2.17 | 118 | 25.69 | (9.2–74) | 16.2 | 977.4 |
| Verona (S) | 205 | 2.92 | 1.17 | 2.94 | 0.53 | 2.55 | 0.53 | 121 | 52.52 | (9.4–110) | 41.5 | 2015.2 |
| Tartu (N) | 259 | 5.61 | 3.07 | 4.63 | 0.00 | 2.76 | 0.00 | 37 | 22.90 | (14–37) | 14.8 | 892.0 |
| South Antwerp (C) | 340 | 4.32 | 1.98 | 3.56 | 1.27 | 2.29 | 1.29 | 86 | 35.27 | (23–57) | 20.8 | 1453.5 |
| Pavia (S) | 192 | 8.80 | 4.96 | 4.17 | 3.85 | 1.92 | 1.91 | 87 | 43.12 | (18–86) | 35.3 | 1782.6 |
| Paris (S) | 433 | 6.00 | 3.71 | 6.26 | 3.46 | 3.53 | 2.54 | 0 | – | 17.8 | 1080.5 | |
| Oviedo (S) | 242 | 8.73 | 4.51 | 10.74 | 5.21 | 6.51 | 1.99 | 135 | 45.61 | (12–143) | 15.9 | 1181.2 |
| Ipswich (C) | 297 | 5.19 | 3.22 | 6.42 | 3.32 | 4.78 | 2.07 | 82 | 30.09 | (0.34–69) | 16.5 | 998.6 |
| Barcelona (S) | 272 | 5.61 | 2.3 | 7.12 | 1.24 | 6.58 | 1.26 | 125 | 76.86 | (41–146) | 22.2 | 1387.9 |
| Albacete (S) | 308 | 14.02 | 7.59 | 9.09 | 4.64 | 4.69 | 3.09 | 142 | 36.88 | (7.1–125) | 13.1 | 1008.5 |
| Goteborg (N) | 505 | 9.38 | 3.81 | 7.54 | 3.82 | 4.13 | 2.75 | 0 | – | 12.6 | 903.4 | |
| Galdakao (S) | 360 | 6.79 | 2.06 | 8.06 | 3.65 | 6.71 | 3.1 | 176 | 40.55 | (5.8–102) | 16.3 | 1584.5 |
| Huelva (S) | 204 | 14.76 | 5.54 | 11.76 | 8.52 | 5.42 | 5.95 | 59 | 35.34 | (13–98) | 17.3 | 1557.8 |
| Umea (N) | 421 | 8.17 | 4.17 | 6.7 | 2.08 | 4.59 | 1.07 | 171 | 6.03 | (0.34–20) | 5.6 | 414.8 |
| Grenoble (S) | 384 | 5.51 | 2.12 | 5.21 | 3.03 | 3.5 | 1.97 | 0 | – | 19.0 | 887.7 | |
| Reykjavik (N) | 460 | 5.21 | 2.33 | 5.9 | 1.71 | 4.51 | 1 | 82 | 12.82 | (0.34–29) | 3.7 | 155.3 |
| Uppsala (N) | 517 | 6.47 | 2.81 | 4.66 | 1.47 | 3.27 | 1.31 | 0 | – | 10.4 | 752.1 | |
| Total | 6824 | 6.53 | 3.20 | 6.07 | 2.80 | 3.96 | 1.93 | 1634 | 38.22 | (0.34–146) | 19.12 | 1167.07 |
*Ordered by participation rate in the follow up.
†New onset among those without these symptoms at baseline.
Geographical area: N, North; C, Centre; S, South.