Association between changes in lung function and cumulative exposure of wood dust in the cohort, stratified by sex and adjusted for confounders in linear regression analyses
| Independent variables | Subjects n | Outcome variables | |||
| ΔFEV1 | ΔFVC | ||||
| β±se | p-value | β±se | p-value | ||
| Male workers | 925 | ||||
| Wood dust exposure | |||||
| 2.97–3.74 mg·yr·m−3 # | -4.56±3.84 | 0.24 | -8.19±4.14 | 0.05 | |
| 3.75–4.71 mg·yr·m−3 # | -5.17±3.75 | 0.17 | -4.25±4.04 | 0.29 | |
| >4.71 mg·yr·m−3 # | -0.25±3.78 | 0.95 | -2.10±4.07 | 0.61 | |
| Smoking history | |||||
| <7 pack-yrs in period¶ | -6.58±3.30 | 0.05 | -3.32±3.55 | 0.35 | |
| ≥7 pack-yrs in period¶ | -16.62±3.61 | 0.00 | -11.90±3.89 | 0.00 | |
| Female workers | 274 | ||||
| Wood dust exposure | |||||
| 2.97–3.74 mg·yr·m−3 # | -1.80±6.29 | 0.78** | -3.44±6.50 | 0.60+ | |
| 3.75–4.71 mg·yr·m−3 # | -14.50±7.05 | 0.04** | -18.33±7.28 | 0.01+ | |
| >4.71 mg·yr·m−3 # | -24.97±9.59 | 0.01** | -14.77±9.90 | 0.14+ | |
| Smoking history | |||||
| <7 pack-yrs in period¶ | -5.17±5.50 | 0.35 | -9.40±5.67 | 0.10 | |
| ≥7 pack-yrs in period¶ | -26.81±5.98 | 0.00 | -23.82±6.18 | 0.00 | |
ΔFEV1: mL annual change in forced expiratory volume in one second; ΔFVC: mL annual change in forced vital capacity. Additional variables in the final models: height, weight-gain, age. #: with reference to the wood dust exposure group 0–2.96 mg·yr·m−3 which included reference workers; ¶: with reference to nonsmokers (never smoker and ex-smokers who stopped smoking >2 yrs prior to the baseline study). *: p<0.01 test for trend; +: p = 0.01 test for trend.