Camp Pat G, Coxson Harvey O, Levy Robert D, Pillai Sreekumar G, Anderson Wayne, Vestbo Jørgen, Kennedy Susan M, Silverman Edwin K, Lomas David A, Paré Peter D
James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, University of British Columbia, Vancouver, BC, Canada.
James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, University of British Columbia, Vancouver, BC, Canada; Department of Radiology, University of British Columbia, Vancouver, BC, Canada.
Chest. 2009 Dec;136(6):1480-1488. doi: 10.1378/chest.09-0676. Epub 2009 Jul 17.
The authors of previous reports have suggested that women are more susceptible to cigarette smoke and to an airway-predominant COPD phenotype rather than an emphysema-predominant COPD phenotype. The purpose of this study was to test for sex differences in COPD phenotypes by using high-resolution CT (HRCT) scanning in male and female smokers with and without COPD.
All subjects completed spirometry and answered an epidemiologic respiratory questionnaire. Inspiratory HRCT scans were obtained on 688 smokers enrolled in a family-based study of COPD. Emphysema was assessed by using a density mask with a cutoff of -950 Hounsfield units to calculate the low-attenuation area percentage (LAA%) and by the fractal value D, which is the slope of a power law analysis defining the relationship between the number and size of the emphysematous lesions. Airway wall thickness was assessed by calculating the square root of the airway wall area (SQRTWA) and the percentage of the total airway area taken by the airway wall (WA%) relative to the internal perimeter.
Women had a similar FEV(1) (women, 65.5% +/- 31.9% predicted; men, 62.1% +/- 30.4% predicted; p = 0.16) but fewer pack-years of cigarette smoking (women, 37.8 +/- 19.7 pack-years; men, 47.8 +/- 27.4 pack-years; p < 0.0001). Men had a greater LAA% (24% +/- 12% vs 20% +/- 11%, respectively; p < 0.0001) and larger emphysematous spaces than women, and these differences persisted after adjusting for covariates (weight, pack-years of smoking, current smoking status, center of enrollment, and FEV(1) percent predicted; p = 0.0006). Women had a smaller SQRTWA and WA% after adjusting for covariates (p < 0.0001).
Male smokers have more emphysema than female smokers, but female smokers do not show increased wall thickness compared with men.
既往报告的作者们提出，女性更容易受到香烟烟雾的影响，且更容易出现以气道为主型的慢性阻塞性肺疾病（COPD）表型，而非以肺气肿为主型的COPD表型。本研究的目的是通过对有或无COPD的男性和女性吸烟者进行高分辨率CT（HRCT）扫描，来检测COPD表型中的性别差异。
所有受试者均完成肺功能测定，并回答一份流行病学呼吸问卷。对参与一项基于家庭的COPD研究的688名吸烟者进行吸气HRCT扫描。通过使用阈值为-950亨氏单位的密度掩膜来计算低衰减面积百分比（LAA%），并通过分形值D（即定义肺气肿病变数量与大小之间关系的幂律分析的斜率）来评估肺气肿。通过计算气道壁面积的平方根（SQRTWA）以及气道壁占气道总面积的百分比（WA%，相对于内周长）来评估气道壁厚度。
女性的第1秒用力呼气容积（FEV₁）相似（女性为预计值的65.5%±31.9%；男性为预计值的62.1%±30.4%；p = 0.16），但吸烟包年数较少（女性为37.8±19.7包年；男性为47.8±27.4包年；p < 0.0001）。男性的LAA%更高（分别为24%±12%和20%±11%；p < 0.0001），且肺气肿区域比女性更大，在调整协变量（体重、吸烟包年数、当前吸烟状态、入组中心以及预计FEV₁百分比）后，这些差异仍然存在（p = 0.0006）。调整协变量后，女性的SQRTWA和WA%更小（p < 0.0001）。
男性吸烟者比女性吸烟者有更多的肺气肿，但与男性相比，女性吸烟者未表现出气道壁厚度增加。
