van Velzen E, van den Bos J W, Benckhuijsen J A, van Essel T, de Bruijn R, Aalbers R
Dutch Asthmacentre Davos, Switerzland.
Thorax. 1996 Jun;51(6):582-4. doi: 10.1136/thx.51.6.582.
Improvement of allergic asthma is seen at high altitude partly because of low concentrations of allergen, especially house dust mite. To investigate the effect of a hypoallergenic environment (Davos, 1560 m) on airways inflammation, the changes in bronchial hyperresponsiveness measured with methacholine and adenosine 5'-monophosphate (AMP), blood eosinophils, eosinophil cationic protein (ECP), and serum IgE were studied.
In 16 allergic asthmatic children tests were performed on admission and after one month. Medication was kept unchanged during the month of investigation and the patients performed peak expiratory flow (PEF) measurements twice daily.
After one month at high altitude a considerable improvement was seen in the provocative concentration of AMP causing a 20% fall in forced expiratory volume in one second (PC20 AMP), but not with methacholine. There was also a reduction in total blood eosinophils and ECP. No change in serum IgE was observed. Peak flow variability decreased.
After one month at high altitude a reduction in airways inflammation occurs. The results indicate that AMP responsiveness is a more accurate marker of disease activity in relation to inflammation in asthma than methacholine. The benefits of allergen avoidance at high altitude have important clinical implications for children with allergic asthma.
在高海拔地区过敏性哮喘症状有所改善，部分原因是过敏原浓度较低，尤其是屋尘螨。为了研究低过敏原环境（达沃斯，海拔1560米）对气道炎症的影响，我们研究了用乙酰甲胆碱和5'-单磷酸腺苷（AMP）测量的支气管高反应性、血液嗜酸性粒细胞、嗜酸性粒细胞阳离子蛋白（ECP）以及血清IgE的变化。
对16名过敏性哮喘儿童在入院时和一个月后进行了测试。在调查的一个月内药物治疗保持不变，患者每天进行两次呼气峰值流速（PEF）测量。
在高海拔地区待了一个月后，导致一秒用力呼气量下降20%的AMP激发浓度有了显著改善，但乙酰甲胆碱激发浓度未改善。血液嗜酸性粒细胞总数和ECP也有所降低。血清IgE未观察到变化。峰值流速变异性降低。
在高海拔地区待一个月后气道炎症减轻。结果表明，与乙酰甲胆碱相比，AMP反应性是哮喘炎症相关疾病活动的更准确标志物。在高海拔地区避免接触过敏原的益处对过敏性哮喘儿童具有重要的临床意义。
