Selected lung function variables pre- and post-shift (0 and 8 h) in cement production workers, in non-smoking workers and in those without doctor-diagnosed asthma or allergy
| Parameter | Pre-shift (n=91), mean (SD) | Post-shift (n=91), mean (SD) | Cross-shift change | ||
| All workers (n=91), mean (95% CI) | No allergy/asthma (n=70), mean (95% CI) | Non-smokers (n=56), mean (95% CI) | |||
| FVC (litres) | 5.02 (0.91) | 4.99 (0.97) | −0.032 (−0.066 to 0.0016) | −0.041 (−0.080 to 0.0023)* | −0.050 (−0.086 to 0.015)* |
| FEV1 (litres) | 3.92 (0.81) | 3.88 (0.81) | −0.037 (−0.072 to 0.0017)* | −0.046 (−0.086 to 0.0063)* | −0.042 (−0.075 to 0.009)* |
| FEV6 (litres)‡ | 4.98 (0.93) | 4.95 (0.97) | −0.034 (−0.070 to 0.0088) | −0.046 (−0.087 to 0.0049)* | −0.053 (−0.090 to 0.017)* |
| FEV1/FVC | 78.1 (7.39) | 78.0 (7.06) | −0.15 (−0.69 to 0.37) | −0.20 (−0.79 to 0.40) | −0.034 (−0.58 to 0.51) |
| PEF (l/s) | 9.68 (1.69) | 9.73 (1.82) | 0.056 (−0084 to 0.20) | 0.053 (−0.11 to 0.21) | −0.0064 (−0.19 to 0.18) |
| FEF25–75% (l/s) | 3.39 (1.31) | 3.22 (1.30) | −0.17 (−0.26 to 0.081)† | −0.18 (−0.28 to 0.070)† | −0.15 (−0.24 to 0.057)* |
| DLco (mmol/min/kPa) | 10.7 (2.1) | 10.5 (2.0) | −0.17 (−0.32 to 0.023)* | −0.052 (−0.11 to 0.23) | −0.25 (−0.46 to 0.04)* |
| KCO (mmol/min/kPa/l) | 1.57 (0.26) | 1.55 (0.26) | −0.02 (−0.044 to 0.010)* | −0.0041 (−0.027 to 0.019) | −0.026 (−0.056 to 0.0035) |
| VA (litres) | 6.85 (1.06) | 6.85 (1.10) | 0.0037 (−0.061 to 0.069) | 0.020 (−0.058 to 0.098) | −0.015 (−0.10 to 0.072) |
↵* Significantly changed from before work shift, p<0.05.
↵† p<0.001.
↵‡ n=89.
DLCO, carbon dioxide diffusion capacity; FEF, forced mid-expiratory flow rate; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; KCO, carbon monoxide transfer per unit effective alveolar volume; PEF, peak expiratory flow; VA, alveolar volume.