[Effects on flow volume curve accompanied by aging--with emphasis on the relation between the change and FEV1.0%].
Changes in respiratory function were compared. The results obtained were as follows. Subjects selected were 462 normal healthy male adults with no disorders in respiratory and circulatory systems, of whom forced expiratory volume in 1 second (FEV1.0%) and peak flow (PF), forced expiratory volume in 75% (V75), forced expiratory volume in 50% (V50) and forced expiratory volume in 25% (V25) were determined. 1. Results of each measured value FEV1.0%, PF, V75, V50 and V25 decreased with age. But V50/V25 increased with age Minimum and maximum values were 6.86 and 36.46 in FEV1.0% and V25. 2. Relationship between FEV1.0% and V50/V25. Both FEV1.0% and V50/V25 did not show marked relation till 34 years. Individual variation occurs in 35 to 39 year old group. This current was famous in 40 to 49 year old group. But no individual variations were found over 50 year old. This suggested that aging affects not only large airways but also small airways, and which is accompanied with enlarged peripheral air way resistance and decreased expiratory flow volume
Muraki
H
H
D000328:Adult; D000375:Aging; D000403:Airway Resistance; D006801:Humans; D008875:Middle Aged; D012123:Pulmonary Ventilation