Smith Jaclyn, Owen Emily, Earis John, Woodcock Ashley
North West Lung Centre, South Manchester University Hospitals Trust, Manchester, United Kingdom.
J Allergy Clin Immunol. 2006 Apr;117(4):831-5. doi: 10.1016/j.jaci.2005.09.055. Epub 2006 Feb 7.
Codeine is the standard antitussive treatment to which novel agents are compared. Little is known about the objective effect of any treatments on cough in chronic obstructive pulmonary disease (COPD).
To quantify the effect of codeine on objective cough frequency (quantified as time spent coughing: cough seconds, cs/h), citric acid cough threshold, and subjective measures in a double-blind, placebo-controlled crossover study in COPD.
We studied 21 patients with physician-diagnosed, stable disease who complained of cough (76.9% male; mean age, 67.7 years; mean predicted FEV(1), 53.4%; median smoking history, 43.5 pack-years). Each subject performed a cough challenge (single breath, citric acid), 10-hour daytime ambulatory and overnight cough recordings, subjective cough scores, and visual analog scales at baseline and on 2 study days, 1 week apart. Codeine phosphate 60 mg or matched placebo were given, in random order, at the start of each cough recording (0 and 12 hours).
Median time spent coughing at baseline was 8.27 cs/h (interquartile range [IQR], 5.94-11.67); after placebo treatment, 7.22 cs/h (IQR 4.42-10.40); and after codeine treatment, 6.41 cs/h (IQR 3.86-9.10). Codeine treatment had a significant effect on time spent coughing compared with baseline (P = .02) but not compared with placebo (P = .52). There were no significant differences in cough challenge thresholds (log concentration of tussive agent causing 2 coughs or log concentration of tussive agent causing 5 coughs) or subjective cough measures for codeine compared with placebo.
In this study, codeine was no more effective than placebo in patients with COPD complaining of cough.
Codeine is the antitussive agent to which we compare new treatments; however, in a group of stable patients with COPD, it had no effect on cough frequency over placebo.
可待因是用于对比新型药物的标准镇咳治疗药物。对于慢性阻塞性肺疾病（COPD）中任何治疗方法对咳嗽的客观效果，人们了解甚少。
在一项针对COPD患者的双盲、安慰剂对照交叉研究中，量化可待因对客观咳嗽频率（以咳嗽时间量化：咳嗽秒数，cs/h）、柠檬酸咳嗽阈值及主观指标的影响。
我们研究了21例经医生诊断为病情稳定且主诉咳嗽的患者（男性占76.9%；平均年龄67.7岁；预计FEV(1)平均为53.4%；吸烟史中位数为43.5包年）。每位受试者在基线时以及相隔1周的2个研究日进行咳嗽激发试验（单次呼吸，柠檬酸）、10小时日间动态及夜间咳嗽记录、主观咳嗽评分和视觉模拟量表评估。在每次咳嗽记录开始时（0小时和12小时），随机给予60mg磷酸可待因或匹配的安慰剂。
基线时咳嗽时间中位数为8.27 cs/h（四分位数间距[IQR]，5.94 - 11.67）；安慰剂治疗后为7.22 cs/h（IQR 4.42 - 10.40）；可待因治疗后为6.41 cs/h（IQR 3.86 - 9.10）。与基线相比，可待因治疗对咳嗽时间有显著影响（P = 0.02），但与安慰剂相比无显著差异（P = 0.52）。与安慰剂相比，可待因在咳嗽激发试验阈值（引起2次咳嗽的镇咳剂对数浓度或引起5次咳嗽的镇咳剂对数浓度）或主观咳嗽指标方面无显著差异。
在本研究中，对于主诉咳嗽的COPD患者，可待因并不比安慰剂更有效。
可待因是我们用于对比新治疗方法的镇咳药物；然而，在一组病情稳定的COPD患者中，与安慰剂相比，它对咳嗽频率没有影响。
