Schwartz D A, Landas S K, Lassise D L, Burmeister L F, Hunninghake G W, Merchant J A
University of Iowa, Iowa City.
Ann Intern Med. 1992 Apr 15;116(8):630-5. doi: 10.7326/0003-4819-116-8-630.
To determine whether work-related respiratory symptoms are indicative of underlying lung disease among swine confinement workers and, if so, to identify whether respiratory changes were more indicative of airway or of interstitial lung injury.
Nested case-control study within a population-based longitudinal study.
University hospital.
Study participants were randomly selected from a group of 207 swine confinement workers followed longitudinally. Of these, 43 workers with respiratory symptoms were identified, and 31 were randomly selected for inclusion in this study. Three control groups (swine confinement workers, neighbor farmers, and blue collar workers) without work-related respiratory symptoms were frequency-matched by age, sex, and smoking status to the symptomatic swine confinement workers.
Spirometry and lung volumes, diffusing capacity of carbon monoxide, chest radiograph, methacholine airway challenge, and bronchoalveolar lavage were done. An endobronchial biopsy was done in the last 27 participants evaluated.
Although spirometric measures of airflow were similar between the symptomatic swine confinement workers and the three control groups, swine confinement cases were found to have significant elevations in residual volume (126.5 +/- 28.2 L) when compared to swine confinement controls (115.4 +/- 38.4 L; P less than or equal to 0.05), neighborhood farmer controls (101.1 +/- 29.4 L; P less than or equal to 0.005), and blue collar controls (106.4 +/- 30.4 L; P less than or equal to 0.05). Swine confinement cases also had an enhanced airway response to inhaled methacholine and had thickening of the epithelial basement membrane of the lobar bronchi. No parenchymal injury was observed in the swine confinement cases.
Our findings suggest that swine confinement workers who have work-related respiratory symptoms are at risk for airway, but not parenchymal, lung injury, and that spirometry may not accurately reflect the extent of airway injury.
确定在封闭式养猪场工作的工人中，与工作相关的呼吸道症状是否预示着潜在的肺部疾病；如果是，确定呼吸道变化更倾向于表明气道损伤还是间质性肺损伤。
在一项基于人群的纵向研究中进行巢式病例对照研究。
大学医院。
研究参与者从207名接受纵向随访的封闭式养猪场工人中随机选取。其中，43名有呼吸道症状的工人被识别出来，31名被随机选入本研究。三个无工作相关呼吸道症状的对照组（封闭式养猪场工人、相邻农场主和蓝领工人）按年龄、性别和吸烟状况与有症状的封闭式养猪场工人进行频数匹配。
进行了肺活量测定和肺容积测定、一氧化碳弥散能力测定、胸部X线片检查、乙酰甲胆碱气道激发试验和支气管肺泡灌洗。对最后评估的27名参与者进行了支气管内活检。
尽管有症状的封闭式养猪场工人与三个对照组之间气流的肺活量测定指标相似，但与封闭式养猪场对照组（115.4±38.4升）、相邻农场主对照组（101.1±29.4升）和蓝领对照组（106.4±30.4升）相比，封闭式养猪场病例的残气量显著升高（126.5±28.2升；P≤0.05）。封闭式养猪场病例对吸入的乙酰甲胆碱的气道反应也增强，叶支气管上皮基底膜增厚。在封闭式养猪场病例中未观察到实质损伤。
我们的研究结果表明，有工作相关呼吸道症状的封闭式养猪场工人存在气道损伤风险，但不存在实质损伤风险，并且肺活量测定可能无法准确反映气道损伤的程度。
