Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
Department of Health Policy and Management, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA, USA.
Int J Chron Obstruct Pulmon Dis. 2019 Dec 20;14:2927-2938. doi: 10.2147/COPD.S220164. eCollection 2019.
Bronchodilator responsiveness (BDR) is prevalent in COPD, but its clinical implications remain unclear. We explored the significance of BDR, defined by post-bronchodilator change in FEV (BDR) as a measure reflecting the change in flow and in FVC (BDR) reflecting the change in volume.
We analyzed 2974 participants from a multicenter observational study designed to identify varying COPD phenotypes (SPIROMICS). We evaluated the association of BDR with baseline clinical characteristics, rate of prospective exacerbations and mortality using negative binomial regression and Cox proportional hazards models.
A majority of COPD participants exhibited BDR (52.7%). BDR occurred more often in earlier stages of COPD, while BDR occurred more frequently in more advanced disease. When defined by increases in either FEV or FVC, BDR was associated with a self-reported history of asthma, but not with blood eosinophil counts. BDR was more prevalent in subjects with greater emphysema and small airway disease on CT. In a univariate analysis, BDR was associated with increased exacerbations and mortality, although no significance was found in a model adjusted for post-bronchodilator FEV.
With advanced airflow obstruction in COPD, BDR is more prevalent in comparison to BDR and correlates with the extent of emphysema and degree of small airway disease. Since these associations appear to be related to the impairment of FEV, BDR itself does not define a distinct phenotype nor can it be more predictive of outcomes, but it can offer additional insights into the pathophysiologic mechanism in advanced COPD.
ClinicalTrials.gov: NCT01969344T4.
支气管扩张剂反应性（BDR）在 COPD 中很常见，但其临床意义仍不清楚。我们探讨了 BDR 的意义，将支气管扩张剂后 FEV（BDR）的变化定义为反映流量变化的指标，将 FVC（BDR）的变化定义为反映体积变化的指标。
我们分析了一项多中心观察性研究的 2974 名参与者，该研究旨在确定不同的 COPD 表型（SPIROMICS）。我们使用负二项回归和 Cox 比例风险模型评估了 BDR 与基线临床特征、前瞻性加重和死亡率的关系。
大多数 COPD 患者存在 BDR（52.7%）。BDR 更多见于 COPD 的早期阶段，而在更晚期疾病中更常见。当以 FEV 或 FVC 的增加来定义时，BDR 与自述哮喘史相关，但与血嗜酸性粒细胞计数无关。在 CT 上，BDR 在肺气肿和小气道疾病更严重的患者中更为常见。在单因素分析中，BDR 与加重和死亡率增加相关，但在调整支气管扩张剂后 FEV 的模型中无显著意义。
在 COPD 中，随着气流阻塞的加重，BDR 比 FEV 更常见，与肺气肿程度和小气道疾病程度相关。由于这些关联似乎与 FEV 的损害有关，BDR 本身并不能定义一个独特的表型，也不能更好地预测结局，但它可以为 COPD 晚期的病理生理机制提供更多的见解。
ClinicalTrials.gov：NCT01969344T4。
