Evans D J, Taylor D A, Zetterstrom O, Chung K F, O'Connor B J, Barnes P J
Department of Thoracic Medicine, National Heart and Lung Institute, Imperial College School of Medicine, London, United Kingdom.
N Engl J Med. 1997 Nov 13;337(20):1412-8. doi: 10.1056/NEJM199711133372002.
Inhaled glucosteroids and oral theophylline are widely used to treat asthma. We compared the benefits of adding theophylline to inhaled glucosteroid with those of doubling the dose of inhaled glucosteroid in patients with persistent symptoms despite the use of inhaled glucosteroid.
In a double-blind, placebo-controlled trial, we randomly assigned 62 patients to receive either 400 microg of inhaled budesonide (low-dose budesonide) with 250 or 375 mg of theophylline (depending on body weight) or 800 microg of inhaled budesonide (high-dose budesonide). All doses were given twice daily for three months. Lung function was measured serially, and patients kept records of peak expiratory flow, symptoms, and albuterol use. The effects of treatment on endogenous cortisol levels were also assessed.
Both treatments resulted in improvements in lung function that were sustained throughout the study. As compared with treatment with high-dose budesonide, treatment with low-dose budesonide plus theophylline resulted in greater improvements in forced vital capacity (P=0.03) and forced expiratory volume in one second (P= 0.03). There were significant and similar reductions in beta2-agonist use and the variability of peak expiratory flow, a correlate of bronchial hyperresponsiveness and the severity of asthma. Serum cortisol concentrations were significantly reduced in the group given high-dose budesonide (from a mean [+/-SE] of 18.4+/-2.4 microg per deciliter to 15.9+/-2.1 microg per deciliter, P=0.02) but were unchanged in the other group. The median serum theophylline concentration was 8.7 microg per milliliter (therapeutic range, 10 to 20) among those who received theophylline. Both treatments were well tolerated.
For patients with moderate asthma and persistent symptoms, low-dose inhaled budesonide with theophylline and high-dose inhaled budesonide produced similar benefits. Effects were achieved at theophylline concentrations below the recommended therapeutic range. The addition of low-dose theophylline to inhaled glucosteroid may be preferable to and cheaper than increasing the dose of inhaled glucosteroid.
吸入性糖皮质激素和口服茶碱广泛用于治疗哮喘。对于尽管使用了吸入性糖皮质激素仍有持续症状的患者,我们比较了在吸入性糖皮质激素基础上加用茶碱与将吸入性糖皮质激素剂量加倍的疗效。
在一项双盲、安慰剂对照试验中,我们将62例患者随机分为两组,一组接受400微克吸入布地奈德(低剂量布地奈德)加250或375毫克茶碱(根据体重),另一组接受800微克吸入布地奈德(高剂量布地奈德)。所有剂量均每日给药两次,共三个月。连续测量肺功能,患者记录呼气峰值流速、症状和沙丁胺醇使用情况。还评估了治疗对内源性皮质醇水平的影响。
两种治疗方法均使肺功能在整个研究过程中持续改善。与高剂量布地奈德治疗相比,低剂量布地奈德加茶碱治疗使用力肺活量(P = 0.03)和一秒用力呼气量(P = 0.03)有更大改善。β2受体激动剂的使用和呼气峰值流速的变异性(支气管高反应性和哮喘严重程度的一个相关指标)有显著且相似的降低。高剂量布地奈德组血清皮质醇浓度显著降低(从平均[±标准误]每分升18.4±2.4微克降至15.9±2.1微克,P = 0.02),而另一组无变化。接受茶碱治疗的患者血清茶碱浓度中位数为每毫升8.7微克(治疗范围为10至20)。两种治疗耐受性均良好。
对于中度哮喘且有持续症状的患者,低剂量吸入布地奈德加茶碱与高剂量吸入布地奈德产生相似的疗效。在低于推荐治疗范围的茶碱浓度下即可达到疗效。在吸入性糖皮质激素基础上加用低剂量茶碱可能比增加吸入性糖皮质激素剂量更可取且更便宜。