Individual unadjusted association between chronic phlegm (prevalence in %, 95% CI) at follow up and variables of interest by gender in 3232 males and 3592 females
| Males | p Value trend | Females | p Value trend | |||||
|---|---|---|---|---|---|---|---|---|
| n | Chronic phlegm | (95% CI) | n | Chronic phlegm | (95% CI) | |||
| Age at II (years) | ||||||||
| <35 | 604 | 7.62 | (5.63–10.03) | 668 | 5.09 | (3.55-7.04) | ||
| 35–45 | 1296 | 7.33 | (5.97–8.89) | 1466 | 5.32 | (4.23–6.60) | ||
| >45 | 1310 | 6.18 | (4.94 –7.63) | 0.387 | 1439 | 5.42 | (4.31–6.72) | 0.952 |
| Smoking | ||||||||
| Non-smoker | 912 | 4.06 | (2.87–5.55) | 1216 | 3.54 | (2.57–4.73) | ||
| With passive smoking | 288 | 3.82 | (1.92–6.73) | 405 | 3.46 | (1.90–5.73) | ||
| Former smoker | 962 | 6.13 | (4.70–7.84) | 920 | 4.13 | (2.94–5.63) | ||
| Smoker: <10/day | 420 | 7.62 | (5.27–10.59) | 508 | 6.50 | (4.51–9.00) | ||
| Smoker: 10–20/day | 354 | 12.71 | (9.43–16.64) | 377 | 11.14 | (8.15–14.76) | ||
| Smoker: >20/day | 201 | 16.42 | (11.58–22.28) | <0.001 | 100 | 19.00 | (11.84–28.07) | <0.001 |
| Respiratory infections <5 years | ||||||||
| No | 2666 | 6.41 | (5.51–7.41) | 2954 | 5.18 | (4.41–6.04) | ||
| Yes | 264 | 9.47 | (6.22–13.66) | 0.058 | 337 | 6.23 | (3.90–9.37) | 0.414 |
| Rhinitis | ||||||||
| No | 2371 | 6.11 | (5.18–7.16) | 2501 | 4.36 | (3.59–5.23) | <0.001 | |
| Yes | 825 | 9.21 | (7.33–11.39) | 0.003 | 1059 | 7.65 | (6.12–9.42) | |
| Occupational exposure | ||||||||
| None | 1451 | 5.31 | (4.21–6.59) | 2098 | 5.24 | (4.33–6.29) | ||
| Low | 850 | 7.41 | (5.74–9.38) | 1124 | 5.43 | (4.18–6.92) | ||
| High | 783 | 9.71 | (7.72–12.00) | <0.001 | 161 | 4.35 | (1.77–8.75) | 0.847 |
| Educational level | ||||||||
| Low | 641 | 9.36 | (7.22–11.88) | 771 | 8.04 | (6.22–10.19) | ||
| Medium | 1171 | 7.69 | (6.23–9.36) | 1209 | 5.13 | (3.95–6.53) | ||
| High | 1335 | 5.17 | (4.04–6.50) | 0.001 | 1512 | 4.03 | (3.10–5.15) | <0.001 |
| Social class | ||||||||
| Professional and managerial (ref) | 1000 | 4.20 | (3.04–5.64) | 865 | 3.35 | (2.26–4.78) | ||
| Other non-manual | 1052 | 6.56 | (5.14–8.23) | 1821 | 5.49 | (4.49–6.64) | ||
| Skilled manual | 576 | 10.24 | (7.89–13.01) | 99 | 4.04 | (1.11–10.02) | ||
| Semi/unskilled manual | 416 | 10.10 | (7.37–13.40) | 262 | 8.40 | (5.34–12.44) | ||
| Unclassified | 166 | 6.02 | (2.93–10.80) | <0.001 | 526 | 6.65 | (4.68–9.13) | 0.008 |
| Reported traffic intensity | ||||||||
| Never | 1463 | 6.63 | (5.41–8.03) | 1399 | 4.15 | (3.16–5.33) | ||
| Seldom | 613 | 7.34 | (5.40–9.70) | 734 | 4.36 | (3.00–6.10) | ||
| Frequent | 503 | 8.35 | (6.08–11.12) | 618 | 5.83 | (4.11–7.97) | ||
| Constant | 620 | 6.13 | (4.37–8.32) | 0.466 | 806 | 7.69 | (5.95–9.75) | 0.002 |
| Geographical area | ||||||||
| North | 1241 | 7.30 | (5.77–9.08) | 1451 | 4.79 | (3.62–6.21) | ||
| Centre | 660 | 3.94 | (2.59–5.72) | 716 | 4.75 | (3.31–6.57) | ||
| South | 1309 | 7.72 | (6.33–9.30) | 0.006 | 1406 | 6.40 | (5.18–7.81) | 0.110 |
| NO2 (μg/m3) | ||||||||
| <20 | 166 | 6.02 | (2.93–10.80) | 191 | 3.14 | (1.16–6.71) | ||
| 20– 35 | 186 | 5.91 | (2.99–10.34) | 244 | 4.51 | (2.27–7.92) | ||
| 35– 50 | 208 | 6.73 | (3.73–11.04) | 235 | 4.26 | (2.06–7.69) | ||
| >50 | 180 | 6.67 | (3.49–11.36) | 0.982 | 219 | 8.68 | (5.30–13.22) | 0.052 |
| Season of symptoms report | ||||||||
| Spring | 997 | 6.32 | (4.89–8.01) | 1146 | 4.45 | (3.33–5.81) | ||
| Summer | 566 | 7.07 | (5.10–9.50) | 636 | 4.87 | (3.34–6.85) | ||
| Autumn | 859 | 6.17 | (4.66–7.99) | 914 | 4.70 | (3.43–6.29) | ||
| Winter | 788 | 8.38 | (6.54–10.53) | 0.27 | 877 | 7.41 | (5.77–9.35) | 0.016 |