Prevalence of respiratory symptoms and prevalence ratios (PR) of respiratory symptoms for above versus below median NAL concentrations of total cells and IL8 in waste collectors and controls
| Prevalence ratio | ||||||
|---|---|---|---|---|---|---|
| Prevalence (%) | Total cells | IL8 | ||||
| Control | Collector | Before | After | Before | After | |
| *p=0.05; **p=0.01; †p=0.10; ‡symptoms at any time during the past 12 months, or when shorter, during the time working at the facility; §calculated by adding one person in the diseased group. | ||||||
| Chronic symptoms: | ||||||
| Cough >3 months in past 2 y | 20.0 | 12.8 | 0.79 | 0.45 | 1.26 | 1.98 |
| Cough with phlegm >3 months in past 2 y | 0.0 | 13.0 | 1.30 | 1.54 | >1.47§ | 7.71* |
| Shortness of breath when walking with contemporaries on the flat | 0.0 | 8.5 | 0.63 | 0.53 | 1.89 | 0.53 |
| Wheeze ever | 13.3 | 29.8 | 1.39 | 0.95 | 1.39 | 2.04† |
| Wheeze >1 week in past 2 y | 6.7 | 14.9 | 0.63 | 1.58 | 1.89 | 2.64 |
| Asthma attacks ever | 6.7 | 12.8 | 1.58 | 0.26 | 1.58 | 2.11 |
| Symptoms at any time during the past y:‡ | ||||||
| Cough | 21.4 | 43.2 | 1.02 | 1.80† | 1.40 | 2.52** |
| Cough with phlegm | 14.3 | 37.8† | 1.78 | 2.00† | 2.80† | 2.36* |
| Wheeze in the chest | 14.2 | 21.6 | 1.39 | 1.33 | 1.51 | 4.28* |
| Shortness of breath | 7.1 | 16.2 | 1.48 | 0.80 | 1.61 | 2.44 |
| Dyspnoea | 7.1 | 10.8 | 2.37 | 3.00 | 2.58 | 2.75 |
| Chest tightness | 7.1 | 13.5 | 1.19 | 2.00 | 3.23 | 1.83 |
| Blocked nose | 42.9 | 62.2 | 1.13 | 1.22 | 1.43 | 1.71* |
| Runny nose | 50.0 | 56.8 | 1.25 | 1.50† | 1.16 | 1.59* |
| Itching nose or sneezing | 21.4 | 62.2** | 0.95 | 1.47 | 1.45 | 1.15 |
| Throat irritation | 14.3 | 29.7 | 1.34 | 2.33† | 1.03 | 2.14† |