Gillooly M, Lamb D
Department of Pathology, University of Edinburgh Medical School.
Thorax. 1993 May;48(5):491-5. doi: 10.1136/thx.48.5.491.
The increases in airspace size within the human lung associated with microscopic emphysema can be assessed by measuring the airspace wall surface area per unit volume of lung tissue (AWUV). In a previous study the limits of normality of AWUV with age were estimated in lifelong non-smokers by the 95% prediction limits of the regression line for these variables. The aims of this study were to study the incidence of microscopically assessed emphysema in a group of smokers and to examine the influence of smoking habit on the susceptibility to and severity of microscopically assessed emphysema.
AWUV was measured on tissue sections from 125 lung specimens obtained from tobacco smokers (mean age 61.1 (range 33-85) years) with the fast interval processor, a rapid automatic scanning device. The mean AWUV value was calculated for each specimen and this figure was plotted against the age of the subject. The limits of normal AWUV were plotted, and AWUV values below these limits were taken as indicative of microscopically assessed emphysema. Details of the number of cigarettes smoked each day were obtained for 97 of the smokers. These subjects were grouped according to smoking habit: group 1, 1-19 cigarettes/day; group 2, 20-29 cigarettes/day; group 3, at least 30 cigarettes/day. The AWUV results from each of these groups were then assessed.
Mean AWUV decreased with age in this group of smokers, but only 26% had microscopically assessed emphysema, indicating that within the group there were two subgroups of smokers with differing susceptibility to microscopically assessed emphysema. There were no sex differences in the incidence of microscopically assessed emphysema, nor were the incidence and severity increased with increased daily cigarette consumption.
Susceptibility to microscopically assessed emphysema was found to be similar in male and female smokers. Daily cigarette consumption did not appear to be the primary factor influencing the susceptibility to or severity of microscopically assessed emphysema. Susceptibility differences within the smoking population should be taken into consideration in studies of the pathogenesis of emphysema.
与显微镜下肺气肿相关的人类肺内气腔大小增加可通过测量每单位肺组织体积的气腔壁表面积（AWUV）来评估。在先前的一项研究中，通过这些变量回归线的95%预测界限，估算了终身不吸烟者中AWUV随年龄变化的正常范围。本研究的目的是研究一组吸烟者中显微镜下评估的肺气肿发病率，并探讨吸烟习惯对显微镜下评估的肺气肿易感性和严重程度的影响。
使用快速间隔处理器（一种快速自动扫描设备），对从125例吸烟者（平均年龄61.1岁（范围33 - 85岁））获取的肺标本组织切片测量AWUV。计算每个标本的平均AWUV值，并将该数值与受试者年龄作图。绘制正常AWUV的界限，低于这些界限的AWUV值被视为显微镜下评估的肺气肿的指征。97名吸烟者提供了每日吸烟量的详细信息。这些受试者根据吸烟习惯分组：第1组，每天吸1 - 19支烟；第2组，每天吸20 - 29支烟；第3组，每天至少吸30支烟。然后评估这些组中每组的AWUV结果。
在这组吸烟者中，平均AWUV随年龄下降，但只有26%的人有显微镜下评估的肺气肿，这表明该组内存在两个对显微镜下评估的肺气肿易感性不同的吸烟者亚组。显微镜下评估的肺气肿发病率不存在性别差异，每日吸烟量增加也未使发病率和严重程度增加。
发现男性和女性吸烟者对显微镜下评估的肺气肿的易感性相似。每日吸烟量似乎不是影响显微镜下评估的肺气肿易感性或严重程度的主要因素。在肺气肿发病机制的研究中，应考虑吸烟人群中的易感性差异。
