Channing Laboratory and Pulmonary and Critical Care Division, Brigham and Women’s Hospital, Boston, Massachusetts 02115, USA.
Am J Respir Crit Care Med. 2011 Jul 1;184(1):57-63. doi: 10.1164/rccm.201101-0021OC. Epub 2011 Apr 14.
A significant proportion of smokers have lung function impairment characterized by a reduced FEV(1) with a preserved FEV(1)/FVC ratio. These smokers are a poorly characterized group due to their systematic exclusion from chronic obstructive pulmonary disease (COPD) studies.
To characterize the clinical, functional, and radiographic features of Global Initiative for Chronic Obstructive Lung Disease (GOLD)-Unclassified (FEV(1)/FVC ≥ 0.7 and FEV(1) < 80% predicted) and lower limits of normal (LLN)-unclassified (FEV(1)/FVC ≥ LLN and FEV(1) < LLN) subjects compared to smokers with normal lung function and subjects with COPD.
Data from the first 2,500 subjects enrolled in the COPDGene study were analyzed. All subjects had 10 or more pack-years of smoking and were between the ages of 45 and 80 years. Multivariate regression models were constructed to determine the clinical and radiological variables associated with GOLD-Unclassified (GOLD-U) and LLN-Unclassified status. Separate multivariate regressions were performed in the subgroups of subjects with complete radiologic measurement variables available.
GOLD-U smokers account for 9% of smokers in COPDGene and have increased body mass index (BMI), a disproportionately reduced total lung capacity, and a higher proportion of nonwhite subjects and subjects with diabetes. GOLD-U subjects exhibit increased airway wall thickness compared to smoking control subjects and decreased gas trapping and bronchodilator responsiveness compared to subjects with COPD. When LLN criteria were used to define the "unclassified" group, African American subjects were no longer overrepresented. Both GOLD-U and LLN-Unclassified subjects demonstrated a wide range of lung function impairment, BMI, and percentage of total lung emphysema.
Subjects with reduced FEV(1) and a preserved FEV(1)/FVC ratio are a heterogeneous group with significant symptoms and functional limitation who likely have a variety of underlying etiologies beyond increased BMI. Clinical trial registered with www.clinicaltrials.gov (NCT000608764).
很大一部分吸烟者的肺功能受损，其特征是 FEV1 降低，而 FEV1/FVC 比值正常。这些吸烟者是一个特征描述较差的群体，因为他们被系统地排除在慢性阻塞性肺疾病（COPD）研究之外。
描述全球慢性阻塞性肺疾病倡议（GOLD）未分类（FEV1/FVC≥0.7 和 FEV1<80%预计值）和下正常限（LLN）未分类（FEV1/FVC≥LLN 和 FEV1<LLN）与肺功能正常的吸烟者和 COPD 患者相比，这些患者的临床、功能和影像学特征。
分析 COPDGene 研究中前 2500 名受试者的数据。所有受试者的吸烟量超过 10 包年，年龄在 45 至 80 岁之间。构建多元回归模型以确定与 GOLD 未分类（GOLD-U）和 LLN 未分类状态相关的临床和影像学变量。在有完整放射学测量变量的亚组中分别进行多元回归。
GOLD-U 吸烟者占 COPDGene 吸烟者的 9%，其体重指数（BMI）增加，总肺容量不成比例地降低，非白人和患有糖尿病的患者比例较高。与吸烟对照受试者相比，GOLD-U 受试者的气道壁厚度增加，与 COPD 患者相比，气体潴留和支气管扩张剂反应性降低。当使用 LLN 标准定义“未分类”组时，非裔美国人受试者不再过多。GOLD-U 和 LLN 未分类受试者均表现出广泛的肺功能障碍、BMI 和全肺肺气肿百分比。
FEV1 降低且 FEV1/FVC 比值正常的患者是一组异质性群体，具有明显的症状和功能受限，除 BMI 增加外，他们可能还有多种潜在病因。在 www.clinicaltrials.gov（NCT000608764）上注册的临床试验。
