Alpha 1-antitrypsin and lung function in cement workers

The relationship between the serum concentration of alpha 1-antitrypsin (AAT), the concentration of dust at the workplace and lung function abnormalities was examined in 48 male workers occupationally exposed to cement dust. Measurements were performed in all subjects and included ventilatory volumes (FVC, FEV1), airway resistance (Raw), static lung volumes (RV, FRC, TLC), transfer factor for CO and AAT serum concentration. The relationship between lung function, smoking, respirable cement dust exposure, and AAT serum concentration was investigated by the method of multiple linear regression. A statistically significant correlation was observed between AAT blood concentration and respirable dust exposure. The contribution of respirable dust exposure to the description of AAT concentration was positive as was the contribution of Raw. The contributions of transfer CO, smoking and RV/TLC ratio were negative. All the variables considered accounted for approximately 30% of the total variability of the AAT concentration. To conclude, in cement workers the higher AAT serum concentration which is associated with a loss of lung function, and higher respirable cement dust concentration may be part of the defence mechanism against the potential proteolytic activity occurring in occupational dust exposure.