OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.
OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.
Authors: Francisco Franco-Marina; Rosario Fernandez-Plata; Luis Torre-Bouscoulet; Cecilia García-Sancho; Elisa Sanchez-Gallen; David Martinez; Rogelio Perez-Padilla Journal: NPJ Prim Care Respir Med Date: 2014-05-20 Impact factor: 2.871
Authors: Kyung Soo Chung; Ji Ye Jung; Moo Suk Park; Young Sam Kim; Se Kyu Kim; Joon Chang; Joo Han Song Journal: Int J Chron Obstruct Pulmon Dis Date: 2016-08-19