Scottish Centre for Respiratory Research, Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Ninewells Hospital and Medical School, Dundee, Scotland, DD1 9SY, UK.
Lung. 2015 Feb;193(1):47-51. doi: 10.1007/s00408-014-9674-6. Epub 2014 Dec 17.
Guidelines advocate the use of spirometry to assess pulmonary function in asthmatic patients. Commonly used measures include forced expiratory volume in 1 s (FEV1), forced expiratory ratio (FEV1/FVC), and forced mid-expiratory flow between 25 and 75 % of forced vital capacity (FEF25-75). Impulse oscillometry (IOS) is an effort-independent test performed during tidal breathing. IOS may be used to assess the total and central airway resistance at 5 Hz (R5) and 20 Hz (R20), respectively, and hence derive the peripheral airway resistance from the difference (R5-R20). We compared spirometry and IOS as tests of global airway function (i.e., FEV1, FEV1/FVC, R5) and putative measures of small airways function (i.e., FEF25-75, R5-R20) and their relationship to oral steroid and short-acting beta-agonist (SABA) use as surrogates for long-term asthma control.
Spirometry and IOS measurements from physician-diagnosed asthmatics were linked to a health informatics database for oral steroid and SABA use 1 year prior to the index measurements.
Four hundred forty-two patients had both spirometry and IOS, mean FEV1 = 86 % predicted, 94 % on ICS, median dose 800 µg/day. IOS and spirometry measures were equally predictive of impaired asthma control for both oral steroid and SABA use. For oral steroid use, the adjusted odds ratio, OR (95 % CI) is as follows: FEV1 < 80 %: 1.56(0.99-2.47), p = 0.056; FEV1/FVC < 0.70: 1.67(1.03-2.69), p = 0.037; FEF25-75 < 60 %: 1.84(1.18-2.86), p = 0.007; R5 > 150 %: 1.91(1.25-2.95), p = 0.003; and R5-R20 > 0.1 kPa L(-1) s 1.73(1.12-2.66), p = 0.013. For SABA use, the adjusted OR (95 % CI) is as follows: FEV1 < 80 %: 2.22(1.43-3.44), p < 0.001; FEV1/FVC < 0.70: 2.26(1.44-3.57), p < 0.001; FEF25-75 < 60 %: 2.51(1.65-3.82), p < 0.001; R5 > 150 %: 1.76(1.18-2.63), p = 0.006; and R5-R20 > 0.1 kPa L(-1) s: 2.94(1.94-4.46), p < 0.001.
Spirometry or IOS measurements were equally useful as potential markers of asthma control in persistent asthmatic patients.
指南提倡使用肺活量测定法来评估哮喘患者的肺功能。常用的指标包括 1 秒用力呼气量（FEV1）、用力呼气比值（FEV1/FVC）以及用力呼出 25%至 75%肺活量时的中间呼气流速（FEF25-75）。脉冲震荡（IOS）是一种在潮气呼吸时进行的无需用力的测试。IOS 可用于分别评估 5 Hz（R5）和 20 Hz（R20）时的总气道阻力和中央气道阻力，并由此得出外周气道阻力的差值（R5-R20）。我们比较了肺活量测定法和 IOS，以评估气道整体功能（即 FEV1、FEV1/FVC、R5）和可能的小气道功能指标（即 FEF25-75、R5-R20），并将其与口服皮质类固醇和短效β-激动剂（SABA）的使用情况进行了比较，以作为长期哮喘控制的替代指标。
将经医生诊断的哮喘患者的肺活量测定法和 IOS 测量值与健康信息数据库相关联，以了解他们在进行指数测量前 1 年内口服皮质类固醇和 SABA 的使用情况。
共有 442 例患者同时进行了肺活量测定法和 IOS 检查，平均 FEV1 为预计值的 86%，94%的患者使用 ICS，中位剂量为 800 μg/天。IOS 和肺活量测定法的测量结果均能预测口服皮质类固醇和 SABA 使用情况对哮喘控制的影响。对于口服皮质类固醇的使用，调整后的比值比（OR）（95%CI）如下：FEV1 < 80%：1.56（0.99-2.47），p = 0.056；FEV1/FVC < 0.70：1.67（1.03-2.69），p = 0.037；FEF25-75 < 60%：1.84（1.18-2.86），p = 0.007；R5 > 150%：1.91（1.25-2.95），p = 0.003；以及 R5-R20 > 0.1 kPa L(-1) s：1.73（1.12-2.66），p = 0.013。对于 SABA 的使用，调整后的 OR（95%CI）如下：FEV1 < 80%：2.22（1.43-3.44），p < 0.001；FEV1/FVC < 0.70：2.26（1.44-3.57），p < 0.001；FEF25-75 < 60%：2.51（1.65-3.82），p < 0.001；R5 > 150%：1.76（1.18-2.63），p = 0.006；以及 R5-R20 > 0.1 kPa L(-1) s：2.94（1.94-4.46），p < 0.001。
在持续性哮喘患者中，肺活量测定法或 IOS 测量结果同样可作为哮喘控制的潜在标志物。
