Verberne A A, Hop W C, Creyghton F B, van Rooij R W, van den Berg M, de Jongste J C, Kerrebijn K F
Department of Pediatrics, Erasmus University, University Hospital, Rotterdam, The Netherlands.
J Allergy Clin Immunol. 1996 Apr;97(4):938-46. doi: 10.1016/s0091-6749(96)80068-6.
Inhalation of a single dose of the long-acting beta 2-adrenoceptor agonist salmeterol protects against methacholine-induced airway obstruction and other bronchoconstricting stimuli for at least 12 hours. Hypothetically, twice daily dosing of salmeterol may result in continuous protection.
This study was designed to investigate the protective effect of a single dose of salmeterol and of continuous twice daily treatment on airway responsiveness to methacholine.
In a double- blind, parallel study, salmeterol 50 micrograms twice daily was compared with salbutamol 200 micrograms twice daily. Thirty children with mild asthma, who had little or no bronchial obstruction and were hyperresponsive to methacholine (PD20 < or = 150 micro g) were allocated to receive either salmeterol or salbutamol. Airway responsiveness was measured before study entry, 12 hours after a single dose of drug was given, and monthly during 4 months of daily treatment. Measurements were always performed at the same time of the day, 12 hours after the last dose of medication was administered.
No significant differences in FEV 1 were found between treatments at any time point. PD20 significantly increased after the first dose of salmeterol was given (geometric mean, 100 micro g). Geometric mean PD20 values were significantly better during salmeterol treatment than during salbutamol treatment, 52 and 25 micro g, respectively (p = 0.005).
The protection provided by salmeterol during maintenance treatment was less than that provided after the first dose (p <0.001). However, protection did not diminish during the 4-month treatment period and remained significant compared with baseline (p = 0.003).
吸入单剂量长效β2肾上腺素能受体激动剂沙美特罗可预防乙酰甲胆碱诱发的气道阻塞及其他支气管收缩刺激，作用至少持续12小时。据推测，沙美特罗每日两次给药可能会带来持续的保护作用。
本研究旨在调查单剂量沙美特罗及每日两次持续治疗对气道对乙酰甲胆碱反应性的保护作用。
在一项双盲、平行研究中，将每日两次50微克沙美特罗与每日两次200微克沙丁胺醇进行比较。30名轻度哮喘儿童，几乎没有或没有支气管阻塞，对乙酰甲胆碱反应性高（PD20≤150微克），被分配接受沙美特罗或沙丁胺醇治疗。在研究开始前、给予单剂量药物12小时后以及每日治疗4个月期间每月测量气道反应性。测量总是在一天中的同一时间进行，即在最后一剂药物给药12小时后。
在任何时间点，各治疗组之间的FEV1均无显著差异。给予第一剂沙美特罗后，PD20显著增加（几何平均值为100微克）。沙美特罗治疗期间的几何平均PD20值显著优于沙丁胺醇治疗期间，分别为52微克和25微克（p = 0.005）。
沙美特罗在维持治疗期间提供的保护作用小于第一剂后提供的保护作用（p <0.001）。然而，在4个月的治疗期间，保护作用并未减弱，与基线相比仍具有显著意义（p = 0.003）。
