FEV6 and FEV1/FEV6 in Japanese Participants of the Community-Based Annual Health Check: The Takahata Study

Abstract

Background Forced expiratory volume in 6 seconds (FEV6) is becoming a substitute of forced vital capacity (FVC). However, the Japanese predictive equation for FEV6 has not been established, and the validity for the use of FEV1/FEV6 for diagnosing airflow limitation in Japanese has not been confirmed. Methods Subjects aged 40 or older, who had participated in a community-based health check in Takahata, Japan, from 2004 through 2005, were enrolled. The smoking histories of these subjects were investigated using a self-reporting questionnaire. FVC, FEV1, and FEV6 were measured using spirometric machines. Predictive equations of FEV6 were obtained from never-smoking subjects without history of pulmonary diseases by multiple linear regression assay. Results FEV6 and FEV1/FEV6 were significantly correlated with FVC (r=0.998, p<0.001) and FEV1/FVC (r=0.989, p<0.001), respectively. The cutoff values of percent predicted (%) FEV6 and FEV1/FEV6 for discrimination of having the restrictive lung disorder determined by %FVC <0.8 and having the airflow limitation determined by FEV1/FVC <0.7 were 0.80 and 0.72, respectively (%FEV6: sensitivity=0.995, specificity= 0.983, positive predictive value <PPV>=0.832, negative predictive value <NPV>=1.000; FEV1/FEV6: sensitivity=0.942; specificity=0.971; PPV=0.787; NPV=0.993). When the 5th percentile the lower limit of normal values was used as criterion for discrimination of having airflow limitation, sensitivity, specificity, PPV, and NPV of FEV1/FEV6 were 0.932, 0.985, 0.808, and 0.995, respectively. Conclusion The results of the present study suggest that %FEV6 and FEV1/FEV6 are excellent substitutes for %FVC and FEV1/FVC, respectively. We confirmed the validity of the use of FEV6 and FEV1/FEV6 for identifying pulmonary diseases in Japanese individuals.

Peak flow meter with a questionnaire and mini-spirometer to help detect asthma and COPD in real-life clinical practice: a cross-sectional study

“…These differences could be because in most of the previous studies FEV 6 was derived from the same maneuver and using a standard spirometer. 18, 22, 23, 29–31 Comparatively the sensitivities and specificities of FEV 1 / FEV 6 were lower when a mini-spirometer was used. 25, 26 Since, these mini-spirometer devices do not show flow-volume and volume-time graphs for quality assurance, it is possible that, as a result FEV 1 and FEV 6 are often inaccurately measured leading to lower accuracy in detection of OADs.…”

Active case finding strategy for chronic obstructive pulmonary disease with handheld spirometry

“…We also tested the validity of a suggested FEV 1 /FEV 6 <0.72 cut-off for airway limitation reported in studies conducted in Japan and China. [ 23 , 24 ] We chose this value among others because of the similar ethnicity between these and our study population, which is an important consideration for evaluating pulmonary function. [ 25 ] Using this cut-off for our study population, sensitivity was 45.5%, specificity was 89.3%, PPV was 57.1%, and NPV was 83.9%.…”

Impairment of Pulmonary Function is an Independent Risk Factor for Atrial Fibrillation: The Takahata Study

“…Subjects with poor data (according to JRS criteria) were excluded 30. Predictive equations were as described previously 27,31. Subjects whose FEV 1 /FVC was < 70% were identified as having airflow limitation, and those with FVC %predicted <80% were described as having lung restriction.…”