支气管哮喘患者诱导痰嗜酸性粒细胞计数与肺功能和呼出气一氧化氮浓度的关系

目的分析诱导痰嗜酸性粒细胞（EOS）计数与第一秒用力呼气容积（FEV1）和呼出气一氧化氮浓度的关系，并探讨EOS和呼出气一氧化氮水平对治疗方案调整的指导意义。方法收集轻-中度非急性发作期哮喘患者65例（轻度32例，中度33例），经吸入糖皮质激素和长效β2肾上腺素受体激动剂联合治疗1年，随访测定第一秒用力呼气容积占预计值百分比（FEV1％）、最高呼气流速占预计值百分比（PEF％）、诱导痰EOS计数和呼出气一氧化氮浓度，记录哮喘控制测试得分。同时测定21名健康志愿者（对照组）诱导痰EOS计数、FEV1％、PEF％及呼出气一氧化氮浓度。结果共有63例患者完成治疗和随访全程。治疗1～3个月时患者肺功能恢复较快，治疗半年后肺功能仍有缓慢改善。在治疗第3个月时，呼出气一氧化氮水平下降[治疗前（61±25）nmol／L，治疗3个月后（32±19）nmol／L]，差异有统计学意义（q=7．32，P〈0．05）；治疗6个月时呼出气一氧化氮水平降至（22±12）nmol／L，与治疗前及健康对照组比较差异有统计学意义（q=6．63，均P〈0．05）；哮喘组EOS计数为（0．093±0．023）×10^9／L，治疗3个月后为（0．032±0．011）×10^9／L，与治疗前及健康对照比较差异有统计学意义（均P〈0．05）；半年内痰中EOS计数与呼出气一氧化氮水平呈正相关（均P〈0．05）。1、3、6、9、12个月随访时FEV1与呼出气一氧化氮水平呈负相关（r1=-0．537，r3=-0．658，r6=-0．623，r9=-0．537，r12=-0．597，均P〈0．05）。哮喘控制测试得分治疗前与治疗后1、3、6、9、12个月比较差异有统计学意义（F=5．72，P〈0．05）。结论诱导痰EOS与呼出气一氧化氮水平可以较为敏感反映哮喘患者气道炎症，可作为评价疗效及调整治疗方案的指标。

A study on the relevance of eosinophil counts in induced sputum and fractional concentration of exhaled NO and lung functions in asthmatics

Objective To investigate the correlations between eosinophil counts in induced sputum and lung function (FENO) and evaluate these parameters in medication adjustment in patients with asthma.Methods Sixty-five outpatients with mild to moderate persistent asthma ( mild,32 ; moderate,33 ) from January to August 2008 were enrolled in the study.All were treated with combined medications comprising inhaled corticosteroids plus long-acting β2 agonists for 1 year.Lung function (FEV1％ and PEF％ ),eosinophil counts in induced sputum,FENO,and Asthma Control Test (ACT) scores were obtained at regular follow-up intervals.Twenty-one healthy volunteers served as controls,and lung function,eosinophil counts in induced sputum,and FENO were also obtained.Results Sixty-three subjects completed 1-year or longer follow-up.Lung function of 63 subjects recovered quickly in the early days and improved slowly during the following 6 months.FENO decreased from (61 ± 25 ) nmol/L at baseline to ( 32 ± 19 ) nmol/L by the third month (q =7.32,P＜0.05) and to (22 ± 12) nmol/L by the sixth month,which showed significant difference from normal controls [ ( 13 ± 8) nmol/L; q =6.63,P ＜ 0.05 ].Eosinophil counts in induced sputum of the asthma group at baseline were (0.093 ±0.023) × 109/L and decreased to (0.032 ±0.011)× 109/L by the third month,which was significantly different from baseline and normal controls [ (0.005 ±0.003) × 106/ml; q =5.49,P ＜0.05 and q =5.87,P ＜0.05,respectively].FENO showed a significantly positive correlation with eosinophil counts in induced sputum in the first 6 months (r1 =0.612,r2 =0.558,r3 =0.675; all P＜0.05) and a negative correlation with FEV1 (r1 =-0.537,r3 =-0.658,r6 ＝ -0.623,r9 =-0.537,r12 =-0.597 ; all P ＜0.05 ) at any time point of the study.The ACT score of 63 subjects at baseline was 14 ±3,and the scores after treatment for 1,3,6,9,and 12 months were 18 ±5,19 ±7,23 ±2,24 ± 1,and 24 ± 1,respectively; at the same time,significant difference was found ( F =5.72,P ＜ 0.05).Effectiveness was found according to the ACT score only 1 month after treatment.Conclusion The parameters of FENO and eosinophil counts in induced sputum were sensitive in the detection of airway inflammation and may be useful in evaluation of the efficacy of treatment and adjustment of medication regimens.