Soares André Luis Pinto, Rodrigues Sílvia Carla Sousa, Pereira Carlos Alberto de Castro
Hospital do Servidor Público Estadual de São Paulo, São Paulo, SP, Brasil.
J Bras Pneumol. 2008 Jul;34(7):468-72. doi: 10.1590/s1806-37132008000700006.
To evaluate the use of the forced expiratory volume in one second/forced expiratory volume in six seconds (FEV1/FEV6) ratio as an alternative to the FEV1/forced vital capacity (FVC) ratio in the detection of mild airway obstruction.
Reference equations for the Brazilian population in 2006 were used in order to determine the lower limits of normality for the FEV1/FEV6 and FEV1/FVC ratios. The spirometry findings of 155 patients from 20 to 84 years of age were analyzed. All of the patients presented the following: a < 15% difference between predicted and observed FEV1/FVC ratio; an FEV1 > 60% of predicted; and an exhalation time of at least 6 s. The Brazilian Thoracic Society criteria for acceptability and reproducibility in spirometry were met.
Mean values (+/- SD) for FEV1/FEV6 and FEV1/FVC were 73 +/- 4% and 75 +/- 3%, respectively. Using the FEV1/FVC ratio, we identified airflow obstruction in 61 patients, compared with only 46 patients when we used the FEV1/FEV6 ratio, showing a sensitivity of 75% (p < 0.001).
The FEV1/FEV6 ratio has poor sensitivity and should not be used to replace the FEV1/FVC ratio in the diagnosis of mild airway obstruction.
评估使用一秒用力呼气容积/六秒用力呼气容积（FEV1/FEV6）比值替代一秒用力呼气容积/用力肺活量（FEV1/FVC）比值来检测轻度气道阻塞的情况。
使用2006年巴西人群的参考方程来确定FEV1/FEV6和FEV1/FVC比值的正常下限。分析了155名年龄在20至84岁之间患者的肺量计检查结果。所有患者均表现为：预测的和观察到的FEV1/FVC比值之间差异<15%；FEV1>预测值的60%；呼气时间至少6秒。符合巴西胸科学会关于肺量计检查可接受性和可重复性的标准。
FEV1/FEV6和FEV1/FVC的平均值（±标准差）分别为73±4%和75±3%。使用FEV1/FVC比值，我们在61名患者中识别出气流阻塞，而使用FEV1/FEV6比值时只有46名患者，敏感性为75%（p<0.001）。
FEV1/FEV6比值敏感性较差，在诊断轻度气道阻塞时不应被用于替代FEV1/FVC比值。
