Exposed workers | Non-exposed control | P value* | |

Gender (male/female) | 68/0 | 32/16 | <0.01^{*} |

Age (years) (±SD) | 48.3 (11.1) | 38.0 (17.1) | <0.01^{*} |

Exposure (years) (±SD) | 20.5 (10.0) | 0 | |

Body mass index (±SD) | 27.0 (4.0) | 23.7 (2.8) | <0.01 |

VC (%) | 77.4 (18.6)†, n=68 | 97.8 (14.1), n=35 | <0.01 |

TLC (%) | 93.9 (15.4), n=68 | 106.5 (10.7), n=35 | <0.01 |

FVC (%) | 79.0 (19.8), n=68 | 98.3 (13.7), n=44 | <0.01 |

FEV_{1} (%) | 74.6 (22.5), n=68 | 97.9 (14.4), n=45 | <0.01 |

FEV_{1}/FVC | 76.0 (12.1), n=68 | 85.5 (8.9), n=45 | <0.01 |

DLCOsb (%) | 75.8 (17.6), n=66 | 91.4 (11.0), n=36 | <0.01 |

Neutrophils (%) | 68.6 (22.6), n=59 | 46.7 (18.8), n=41 | <0.01 |

Macrophages (%) | 16.8 (18.9), n=59 | 30.4 (23.1), n=42 | <0.01 |

Eosinophils (%) | 1.3 (3.0), n=59 | 8.5 (13.6), n=42 | <0.01 |

Lymphocytes (%) | 12.5 (9.1), n=59 | 12.8 (6.9), n=42 | 0.859 |

The differential cell counts were adjusted to gender and age.

With permission.19

*P<0.05 (for age and body mass index (t-test) and gender (Pearson’s χ

^{2})).†Values are mean (±SD).

DLCOsb, diffusion lung carbon monoxide in a single breath; FEV

_{1}, forced expiratory volume in 1 s; FVC, forced vital capacity; TLC, total lung capacity; VC, vital capacity.