Maximal expiratory flow-volume types in young subjects with past history of nasal allergy and bronchial asthma.

Pulmonary function tests were performed on 252 healthy young subjects free from respiratory and allergic symptoms, and 80 young subjects with past history of nasal allergy (PNA) and 10 subjects with past history of bronchial asthma (PBA). All the subjects were non-smokers. Maximal expiratory flow-volume (MEFV) curves were visually classified into five types (A-E). The percent distribution of type A in healthy subjects was significantly higher than in the PNA group, while the total sum of percentage of types B, C, and D in the PNA group was significantly higher than in the healthy subjects. The percent distribution of type E in the PNA group was similar to that in the healthy subjects. The percent distribution of MEFV types were significantly different between healthy males and healthy females. The percent distribution of types A, B and E were the highest in healthy subjects, PNA and PBA groups, respectively. Conclusively, the difference in the percent distributions of MEFV types was recognized among healthy subjects, PNA and PBA groups.