[Lung compliance in relation to frequency-dependent compliance (FDC) in men exposed to mixed air pollution]

53 males (age 36.8 +/- 7.2 years) with occupational exposure to atmospheric pollutants (low content of silica, sulfur oxides, carbon oxide and heavy metals) for a mean duration of 12.1 +/- 4.8 years were studied. The majority smoked. Dynamic compliance was calculated from esophageal pressure measurements using an esophageal balloon with an electronic transducer and plethysmographic thoracic volume values (Siregnost FD 88 and FD 91S--Siemens). Dynamic compliance (Cdyn) was registered at a ventilatory rate of 15, 30 and 60/min. A significant correlation was found between Cdyn and ventilatory rate in the examined patients in comparison with the control. Cdyn15 = 73.3 +/- 18.8% Cst, Cdyn30 = 54.6 +/- 18.8% Cst, Cdyn60 = 37.4 +/- 14.9% Cst (control Cdyn15 = 85.17% Cst, p < 0.005, Cdyn30 = 82.6 +/- 11.4% Cst, p < 0.001, Cdyn60 = 67.4 +/- 15.8% Cst, p < 0.001). The percentage of abnormal individual Cdyn60 values in the studied group was significantly higher in comparison with the control (p < 0.005). The decrease of Cdyn60 was related to duration of occupational exposure, to mixed atmospheric pollution and history of smoking.