Prediction equations of pulmonary function in male healthy workers exposed to low-level dust in Guangdong Province

Objective The aim of this study was to explore the distribution of pulmonary function of male healthy workers occupationally exposed to very low level dust in Guangdong Province. Moreover,the prediction equations of standardized pulmonary function were established and the reference value was provided. Methods A total of 2 057 male healthy workers in Guangzhou were studied. The distribution of the pulmonary function and affecting factors were analyzed to determine the prediction equation. Results Forced vital capacity(FVC),forced expiratory volume in one second (FEV₁), FEV₁/FVC and maximal mid-expiratory flow curve (MMEF) decreased gradually with age (r=-0.426,-0.528,-0.377,-0.298,respectively, P<0.01). FVC, FEV₁ and MMEF increased gradually with height(r=0.609, 0.585,0.278,respectively, P<0.01). FVC, FEV₁ and FEV₁/FVC were associated with weight(r=0.222, 0.093,-0.248,respectively, P<0.01). The results of multiple linear regression analysis showed that FVC was affected by height, age and weight(β=0.052, -0.018, 0.010, respectively, P<0.01),FEV₁ was affected by height and age (β=0.048,-0.021,P<0.01), MMEF was affected by age and height (β=-0.036, 0.035,repsectively,P<0.01) and FEV₁/FVC was affected by age and height (β=-0.157, -0.137, respectively, P<0.01). The values of the present prediction equations were different from the predicted values of the Southern China area equations announced in 1990. The abnormal rates of FVC and FEV₁ by our prediction equations were higher than the Southern China area equations(χ²=20.83,17.05,respectively,P<0.01). Conclusion The pulmonary function of male healthy workers was related to age,height and weight. Moreover,the present prediction equations of pulmonary function for the workers were more suitable and recommended.