| Popis: |
A random sample of 1700 18-year-old applicants for flight training, who had been free from respiratory symptoms for 1 year or more, was screened for respiratory symptoms in the past. Those who denied such a history had a questionnaire sent to their parents for further verification. Altogether 70 subjects with a past history of "wheezing," "asthma," or "spastic bronchitis" were thus identified. Abnormalities in either FEV1/FVC, Vmax50 or Vmax75 were found in 40% of the subjects with a history of childhood "wheezing," "asthma," or "spastic bronchitis," but only in 8% of controls without such a history. A history of wheezing had no effect on the RV/TLC ratio. The age at which the last bout had occurred had no apparent effect on the degree of flow abnormalities. The most sensitive index for a flow abnormality was Vmax50, which was less than 74% of the predicted values in 2/(30%) of the 70 subjects tested. It is concluded that, in subjects with a history of "wheezing," "asthma," or "spastic bronchitis," flow abnormalities may persist even after prolonged remissions. |
