Riley Craig M, Wenzel Sally E, Castro Mario, Erzurum Serpil C, Chung Kian Fan, Fitzpatrick Anne M, Gaston Benjamin, Israel Elliot, Moore Wendy C, Bleecker Eugene R, Calhoun William J, Jarjour Nizar N, Busse William W, Peters Stephen P, Teague W Gerald, Sorkness Ronald, Holguin Fernando
Department of Medicine, Division of Internal Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America.
Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
PLoS One. 2015 Dec 30;10(12):e0145476. doi: 10.1371/journal.pone.0145476. eCollection 2015.
FEF25-75 is one of the standard results provided in spirometry reports; however, in adult asthmatics there is limited information on how this physiological measure relates to clinical or biological outcomes independently of the FEV1 or the FEV1/FVC ratio.
To determine the association between Hankinson's percent-predicted FEF25-75 (FEF25-75%) levels with changes in healthcare utilization, respiratory symptom frequency, and biomarkers of distal airway inflammation.
In participants enrolled in the Severe Asthma Research Program 1-2, we compared outcomes across FEF25-75% quartiles. Multivariable analyses were done to avoid confounding by demographic characteristics, FEV1, and the FEV1/FVC ratio. In a sensitivity analysis, we also compared outcomes across participants with FEF25-75% below the lower limit of normal (LLN) and FEV1/FVC above LLN.
Subjects in the lowest FEF25-75% quartile had greater rates of healthcare utilization and higher exhaled nitric oxide and sputum eosinophils. In multivariable analysis, being in the lowest FEF25-75% quartile remained significantly associated with nocturnal symptoms (OR 3.0 [95%CI 1.3-6.9]), persistent symptoms (OR 3.3 [95%CI 1-11], ICU admission for asthma (3.7 [1.3-10.8]) and blood eosinophil % (0.18 [0.07, 0.29]). In the sensitivity analysis, those with FEF25-75% <LLN had significantly more nocturnal and persistent symptoms, emergency room visits, higher serum eosinophil levels and increased methacholine responsiveness.
After controlling for demographic variables, FEV1 and FEV1/FVC, a reduced FEF25-75% is independently associated with previous ICU admission, persistent symptoms, nocturnal symptoms, blood eosinophilia and bronchial hyperreactivity. This suggests that in some asthmatics, a reduced FEF25-75% is an independent biomarker for more severe asthma.
用力呼气流量25%-75%（FEF25-75）是肺功能检查报告中提供的标准结果之一；然而，在成年哮喘患者中，关于这一生理学指标如何独立于第一秒用力呼气容积（FEV1）或FEV1/用力肺活量（FVC）比值与临床或生物学结局相关的信息有限。
确定汉金森预测百分比FEF25-75（FEF25-75%）水平与医疗保健利用变化、呼吸道症状频率以及远端气道炎症生物标志物之间的关联。
在参与重度哮喘研究项目1-2的受试者中，我们比较了FEF25-75%四分位数区间的结局。进行多变量分析以避免人口统计学特征、FEV1和FEV1/FVC比值造成的混杂影响。在一项敏感性分析中，我们还比较了FEF25-75%低于正常下限（LLN）且FEV1/FVC高于LLN的受试者的结局。
FEF25-75%最低四分位数区间的受试者医疗保健利用率更高，呼出一氧化氮和痰液嗜酸性粒细胞水平更高。在多变量分析中，处于FEF25-75%最低四分位数区间仍与夜间症状（比值比[OR]3.0[95%置信区间（CI）1.3-6.9]）、持续性症状（OR 3.3[95%CI 1-11]）、因哮喘入住重症监护病房（ICU）（3.7[1.3-10.8]）以及血液嗜酸性粒细胞百分比（0.18[0.07, 0.29]）显著相关。在敏感性分析中，FEF25-75%<LLN的受试者夜间和持续性症状显著更多、急诊就诊次数更多、血清嗜酸性粒细胞水平更高且乙酰甲胆碱反应性增加。
在控制了人口统计学变量、FEV1和FEV1/FVC之后，FEF25-75%降低与既往ICU入住、持续性症状、夜间症状、血液嗜酸性粒细胞增多和支气管高反应性独立相关。这表明在一些哮喘患者中，FEF25-75%降低是更严重哮喘的独立生物标志物。
