Occupational and Environmental Medicine, School of Public Health and Community Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.
Clin Physiol Funct Imaging. 2021 Mar;41(2):181-191. doi: 10.1111/cpf.12684. Epub 2020 Dec 22.
Chronic airflow limitation (CAL) can be defined as fixed ratio of forced expiratory volume in 1 s (FEV )/forced vital capacity (FVC) < 0.70 after bronchodilation. It is unclear which is the most optimal ratio in relation to respiratory morbidity. The aim was to investigate to what extent different ratios of FEV /FVC were associated with any respiratory symptom. In a cross-sectional general population study, 15,128 adults (50-64 years of age), 7,120 never-smokers and 8,008 ever-smokers completed a respiratory questionnaire and performed FEV and FVC after bronchodilation. We calculated different ratios of FEV /FVC from 0.40 to 1.0 using 0.70 as reference category. We analysed odds ratios (OR) between different ratios and any respiratory symptom using adjusted multivariable logistic regression. Among all subjects, regardless of smoking habits, the lowest odds for any respiratory symptom was at FEV /FVC = 0.82, OR 0.48 (95% CI 0.41-0.56). Among never-smokers, the lowest odds for any respiratory symptom was at FEV /FVC = 0.81, OR 0.53 (95% CI 0.41-0.70). Among ever-smokers, the odds for any respiratory symptom was lowest at FEV /FVC = 0.81, OR 0.43 (95% CI 0.16-1.19), although the rate of inclining in odds was small in the upper part, that is FEV /FVC = 0.85 showed similar odds, OR 0.45 (95% CI 0.38-0.55). We concluded that the odds for any respiratory symptoms continuously decreased with higher FEV /FVC ratios and reached a minimum around 0.80-0.85, with similar results among never-smokers. These results indicate that the optimal threshold associated with respiratory symptoms may be higher than 0.70 and this should be further investigated in prospective longitudinal studies.
慢性气流受限（CAL）可定义为支气管扩张后 1 秒用力呼气量（FEV ）/用力肺活量（FVC）的固定比值<0.70。目前尚不清楚与呼吸发病率相关的最佳比值是多少。目的是研究不同的 FEV/FVC 比值与任何呼吸系统症状的关系。在一项横断面的一般人群研究中，共有 15128 名成年人（50-64 岁）、7120 名从不吸烟者和 8008 名曾吸烟者完成了一份呼吸问卷，并在支气管扩张后进行了 FEV 和 FVC 的检测。我们使用 0.70 作为参考类别，计算了 0.40 至 1.0 之间不同的 FEV/FVC 比值。我们使用调整后的多变量逻辑回归分析了不同比值与任何呼吸系统症状之间的比值比（OR）。在所有研究对象中，无论吸烟习惯如何，FEV/FVC 比值最低（0.82）时，任何呼吸系统症状的几率最低，比值比（OR）为 0.48（95%可信区间 0.41-0.56）。从不吸烟者中，FEV/FVC 比值最低（0.81）时，任何呼吸系统症状的几率最低，比值比（OR）为 0.53（95%可信区间 0.41-0.70）。在曾吸烟者中，FEV/FVC 比值最低（0.81）时，任何呼吸系统症状的几率最低，比值比（OR）为 0.43（95%可信区间 0.16-1.19），尽管在较高比值时，几率的上升幅度较小，即 FEV/FVC 比值为 0.85 时，几率相似，比值比（OR）为 0.45（95%可信区间 0.38-0.55）。我们得出结论，随着 FEV/FVC 比值的增加，任何呼吸系统症状的几率呈连续下降趋势，在 0.80-0.85 左右达到最低值，从不吸烟者中也得到了类似的结果。这些结果表明，与呼吸症状相关的最佳阈值可能高于 0.70，这需要在前瞻性纵向研究中进一步探讨。
