Enarson D A, Vedal S, Chan-Yeung M
Respiratory Division, University of British Columbia, Vancouver General Hospital.
Clin Invest Med. 1988 Jun;11(3):193-7.
Bronchial reactivity to methacholine and to grain dust were determined in a group of grainhandlers whose spirometry was being studied prospectively. Six workers showed specific bronchial responses to grain dust (indicative of occupational asthma), 21 did not show reactivity to grain dust but had bronchial hyperreactivity to methacholine and 40 had neither. Those with hyperreactivity were older, had lower FEV1 at initial examination and were more likely to experience a significant decline in FEV1 over a single working shift. Over 6 years of follow-up, those with hyperreactivity were not more likely to leave work and although they showed a more rapid decline in lung function over the period, because of the small number of individuals studied the difference between those with and without bronchial hyperreactivity was not significant. Among those with hyperreactivity to methacholine, there was a significant positive association between change in FEV1 over a single workshift and change in FEV1 over six years of followup, not seen in those without hyperreactivity to methacholine. Moreover, reactivity to methacholine was a stable observation over 6 years in the majority of studied individuals. We conclude that in the presence of bronchial hyperreactivity to methacholine, change in FEV1 over a single workshift more precisely predicts the trend in FEV1 over time in grainhandlers.
对一组正在接受前瞻性肺功能测定的谷物搬运工人，测定了其对乙酰甲胆碱和谷物粉尘的支气管反应性。6名工人对谷物粉尘表现出特异性支气管反应（提示职业性哮喘），21名工人对谷物粉尘无反应性，但对乙酰甲胆碱有支气管高反应性，40名工人两者均无。有高反应性的工人年龄较大，初次检查时FEV1较低，且在单个工作班次期间FEV1更有可能出现显著下降。在6年的随访中，有高反应性的工人离职可能性并未增加，尽管在此期间他们的肺功能下降更快，但由于研究的个体数量较少，有支气管高反应性和无支气管高反应性的工人之间的差异并不显著。在对乙酰甲胆碱有高反应性的工人中，单个工作班次期间FEV1的变化与6年随访期间FEV1的变化之间存在显著正相关，而在对乙酰甲胆碱无高反应性的工人中未观察到这种情况。此外，在大多数研究个体中，对乙酰甲胆碱的反应性在6年期间是一个稳定的观察结果。我们得出结论，在存在对乙酰甲胆碱的支气管高反应性时，单个工作班次期间FEV1的变化能更准确地预测谷物搬运工人FEV1随时间的变化趋势。
