Kamada Takahiro, Kaneko Masahiro, Tomioka Hiromi
Department of Respiratory Medicine, Kobe City Medical Center West Hospital, Kobe, Japan.
Int J Chron Obstruct Pulmon Dis. 2017 Feb 3;12:509-516. doi: 10.2147/COPD.S124828. eCollection 2017.
Forced oscillation technique (FOT) has been reported to be useful in the evaluation and management of obstructive lung disease, including COPD. To date, no data are available concerning long-term changes in respiratory system impedance measured by FOT. Additionally, although exacerbations have been reported to be associated with excessive lung function decline in COPD, the impact of exacerbations on the results of FOT has not been demonstrated. The aim of this study was to investigate the longitudinal changes in respiratory system impedance and the influence of exacerbations thereon.
Between March 2011 and March 2012, outpatients who attended Kobe City Medical Center West Hospital with a diagnosis of COPD were assessed for eligibility. Baseline patient characteristics (age, sex, body mass index, smoking history, current smoking status, COPD stage), lung function (post-bronchodilator forced expiratory volume in 1 second [FEV]), blood tests (neutrophils and eosinophils), FOT, and COPD assessment test results were collected at enrollment. Lung function and FOT were examined every 6 months until March 2016. Annual changes in FEV and FOT parameters were obtained from the slope of the linear regression curve. The patients were divided into 2 groups based on exacerbation history.
Fifty-one of 58 patients with COPD were enrolled in this study. The median follow-up period was 57 (52-59) months. Twenty-five (49%) patients experienced exacerbations. A significant annual decline in FEV and respiratory system impedance were shown. Additionally, annual changes in FEV, respiratory system resistance at 5 Hz, respiratory system reactance at 5 Hz, and resonant frequency were greater in patients with exacerbations than in those without exacerbations.
Exacerbations of COPD lead not only to a decline in lung function but also to an increase in respiratory system impedance.
据报道，强迫振荡技术（FOT）在包括慢性阻塞性肺疾病（COPD）在内的阻塞性肺疾病的评估和管理中很有用。迄今为止，尚无关于通过FOT测量的呼吸系统阻抗长期变化的数据。此外，虽然据报道急性加重与COPD患者肺功能过度下降有关，但急性加重对FOT结果的影响尚未得到证实。本研究的目的是调查呼吸系统阻抗的纵向变化及其急性加重对此的影响。
在2011年3月至2012年3月期间，对就诊于神户市立医疗中心西医院且诊断为COPD的门诊患者进行资格评估。在入组时收集患者的基线特征（年龄、性别、体重指数、吸烟史、当前吸烟状态、COPD分期）、肺功能（支气管扩张剂后1秒用力呼气容积[FEV]）、血液检查（中性粒细胞和嗜酸性粒细胞）、FOT以及COPD评估测试结果。在2016年3月之前，每6个月检查一次肺功能和FOT。从线性回归曲线的斜率获得FEV和FOT参数的年度变化。根据急性加重病史将患者分为两组。
58例COPD患者中有51例纳入本研究。中位随访期为57（52 - 59）个月。25例（49%）患者经历了急性加重。结果显示FEV和呼吸系统阻抗有显著的年度下降。此外，有急性加重的患者FEV、5Hz时的呼吸系统阻力、5Hz时的呼吸系统电抗和共振频率的年度变化大于无急性加重的患者。
COPD急性加重不仅导致肺功能下降，还导致呼吸系统阻抗增加。
