Department of Pulmonology, İstanbul University Cerrahpaşa School of Medicine, İstanbul, Turkey.
Department of Pulmonology, Uludag University School of Medicine, Bursa, Turkey.
Balkan Med J. 2017 Apr 5;34(2):113-118. doi: 10.4274/balkanmedj.2015.0857.
Several recent studies have suggested that 1 minus-forced expiratory volume expired in 3 seconds / forced vital capacity (1-FEV3/FVC) may be an indicator of distal airway obstruction and a promising measure to evaluate small airways dysfunction.
To investigate the associations of 1-FEV3/FVC with the spirometric measures and lung volumes that assess small airways dysfunction and reflects hyperinflation and air trapping.
Retrospective cross-sectional study.
Retrospective assessment of a total of 1110 cases who underwent body plethysmographic lung volume estimations between a time span from 2005 to 2012. Patients were assigned into two groups: firstly by FEV1/FVC (FEV1/FVC <70% vs. FEV1/FVC ≥70%); secondly by FEV3/FVC < lower limits of normal (LLN) (FEV3/FVC < LLN vs. FEV3/FVC ≥ LLN). Spirometric indices and lung volumes measured by whole-body plethysmography were compared in groups. Also the correlation of spirometric indices with measured lung volumes were assessed in the whole-study population and in subgroups stratified according to FEV1/FVC and FEV3/FVC.
Six hundred seven (54.7%) were male and 503 (45.3%) were female, with a mean age of 52.5±15.6 years. Mean FEV3/FVC and 1-FEV3/FVC were 87.05%, 12.95%, respectively. The mean 1-FEV3/FVC was 4.9% in the FEV1/FVC ≥70% group (n=644) vs. 24.1% in the FEV1/FVC <70% group (n=466). A positive correlation was found between 1-FEV3/FVC and residual volume (r=0.70; p<0.0001), functional residual capacity-pleth (r=0.61; p<0.0001), and total lung capacity (r=0.47; p<0.0001). 1-FEV3/FVC was negatively correlated with forced expiratory flow25-75 (r=-0.84; p<0.0001). The upper limit of 95% confidence interval for 1-FEV3/FVC was 13.7%. 1-FEV3/FVC showed significant correlations with parameters of air trapping and hyperinflation measured by whole-body plethysmography. Importantly, these correlations were higher in study participants with FEV1/FVC <70% or FEV3/FVC < LLN compared to those with FEV1/FVC ≥70% or FEV3/FVC ≥ LLN, respectively.
1-FEV3/FVC can be easily calculated from routine spirometric measurements. 1-FEV3/FVC is a promising marker of air trapping and hyperinflation. We suggest that 1-FEV3/FVC is complementary to FEV1/FVC and recommend clinicians to routinely report and evaluate together with FEV1/FVC during spirometry.
最近的几项研究表明，1 秒用力呼气容积占用力肺活量的百分比（1-FEV3/FVC）可能是远端气道阻塞的指标，也是评估小气道功能障碍的有前途的指标。
探讨 1-FEV3/FVC 与评估小气道功能障碍和反映过度充气和空气潴留的肺量计指标和肺容积之间的关系。
回顾性横断面研究。
回顾性评估了 2005 年至 2012 年间共 1110 例接受全身体积描记法肺容积估计的患者。患者分为两组：首先根据 FEV1/FVC（FEV1/FVC<70% 与 FEV1/FVC≥70%）；其次根据 FEV3/FVC<下限时（FEV3/FVC<LLN 与 FEV3/FVC≥LLN）。比较两组的肺量计指标和全身体积描记法测量的肺容积。还评估了整个研究人群以及根据 FEV1/FVC 和 FEV3/FVC 分层的亚组中肺量计指标与测量肺容积的相关性。
607 例（54.7%）为男性，503 例（45.3%）为女性，平均年龄为 52.5±15.6 岁。平均 FEV3/FVC 和 1-FEV3/FVC 分别为 87.05%和 12.95%。FEV1/FVC≥70%组（n=644）的平均 1-FEV3/FVC 为 4.9%，FEV1/FVC<70%组（n=466）为 24.1%。1-FEV3/FVC 与残气量（r=0.70；p<0.0001）、功能残气量-pleth（r=0.61；p<0.0001）和总肺容量（r=0.47；p<0.0001）呈正相关。1-FEV3/FVC 与用力呼出 25-75 的流速（r=-0.84；p<0.0001）呈负相关。1-FEV3/FVC 的 95%置信区间上限为 13.7%。1-FEV3/FVC 与全身体积描记法测量的空气潴留和过度充气的参数有显著相关性。重要的是，在 FEV1/FVC<70%或 FEV3/FVC<LLN 的研究参与者中，这些相关性明显高于 FEV1/FVC≥70%或 FEV3/FVC≥LLN 的参与者。
1-FEV3/FVC 可从常规肺量计测量中轻松计算得出。1-FEV3/FVC 是空气潴留和过度充气的有前途的标志物。我们建议 1-FEV3/FVC 是 FEV1/FVC 的补充，并建议临床医生在肺量计时常规报告和评估，同时评估 FEV1/FVC。
