Characteristics of the study population of grain and animal feed industry workers in Norway
| Exposed workers (n=68) | Referents (n=36) | |
|---|---|---|
| Age (year)* | 41 (16–61) | 46 (21–60) |
| Height (cm)* | 179 (162–196) | 176 (156–191) |
| Weight (kg)* | 90 (63–123) | 83 (55–109) |
| Body mass index (kg/m2)* | 28 (21–38) | 27 (21–38) |
| Never-smoker (%)† | 43 | 44 |
| Current smoker (%)† | 27 | 17 |
| Ex-smoker (%)† | 31 | 39 |
| Male/female (%) | 94/6 | 83/17 |
| Atopy‡ (%)† | 22 | 23 |
| Physician-diagnosed asthma§ | 3 (4) | 2 (6) |
| Farm childhood (%)†¶ | 35 | 42 |
| Farm or animals at home (%)† | 16 | 28 |
| RPE use (%)† | 16 | 0 |
| FVC (L)** | 5.1 (3.3–8.4) | 4.9 (3.3–7.1) |
| FVC% pred** | 96 (66–133) | 100 (80–122) |
| FEV1 (L)** | 4.0 (2.7–6.6) | 3.7 (1.7–5.4) |
| FEV1% pred** | 92 (68–127) | 93 (51–120) |
| FEV1/FVC%** | 78 (68–90) | 76 (48–89) |
| DL,CO (adj) (mmol/min/kPa)** | 9.7 (6.3–14.6) | 8.8 (3.3–12.6) |
| DL,CO % pred** | 86 (32–149) | 85 (58–127) |
| D-factor** | 0.6 (0.1–1.8) | 0.5 (0.1–1.2) |
*AM (minimum–maximum).
†Prevalence.
‡Positive serum reaction towards inhalation panel.
§Self-reported, expressed as n (%).
¶Included one exposed worker that moved to a farm in his youth.
**Lung function at baseline is expressed as AM (minimum–maximum) of actual values and mean per cent of predicted values according to age, height and weight, whereas the nose congestion factor is expressed as AM (minimum–maximum) of a relative value. AM, arithmetic mean; CO, carbon monoxide; DL,CO (adj), CO diffusion capacity of the lung adjusted for the haemoglobulin concentration; D-factor, decongestion factor of the nose; FEV1, forced expired volume in the first second; FVC, forced vital capacity; RPE, respiratory protective equipment.