Mehta Vinay, Stokes Jeffrey R, Berro Abdo, Romero Francisco A, Casale Thomas B
Allergy, Asthma & Immunology Associates, PC, Lincoln, Nebraska, USA.
Ann Allergy Asthma Immunol. 2009 Jul;103(1):31-7. doi: 10.1016/S1081-1206(10)60140-8.
Exhaled nitric oxide (F(ENO)) and exhaled breath condensate (EBC) are noninvasive markers that directly measure airway inflammation and may potentially be useful in assessing asthma control and response to therapy.
To examine the time-dependent effects of inhaled corticosteroids on F(ENO) and EBC markers concomitantly with lung function and bronchial hyperresponsiveness.
Eleven steroid-naive adults with mild-to-moderate persistent asthma were treated with mometasone furoate dry powder inhaler, 400 microg/d, for 8 weeks, followed by a 4-week washout. Forced expiratory volume in 1 second (FEV1), the concentration of methacholine calculated to cause a 20% decline in FEV1 (PC20), F(ENO), EBC pH, and EBC nitrite measurements before, during, and after treatment were analyzed and compared.
The mean (SEM) FEV1 increased from 3.01 (0.13) L (82% predicted) to 3.24 (0.18) L (87% predicted) by week 8 (P < .05). The PC20 level increased from 1.28 (0.31) mg/mL to 2.99 (0.51) mg/mL by treatment week 8 (P < .05) and remained relatively stable through washout week 4 (P < .05). The F(ENO) level decreased from 31.1 (4.1) ppb to 20.6 (4.5) ppb by treatment week 1 (P < .01), remained low through treatment week 8 (P < .01), then trended back to the baseline level by washout week 1 (P < .01). The median EBC pH increased from 7.81 (interquartile range, 7.49-8.09) to 8.02 (interquartile range, 7.87-8.12) by treatment week 4, but did not achieve statistical significance. The EBC nitrite level decreased from 17.6 (1.6) microM to 9.3 (0.9) microM by treatment week 8 (P < .01), and remained low throughout washout week 4 (P < .05). There was a negative correlation between F(ENO) and PC20 (Spearman rank correlation coefficient = -0.50, P < .001).
The F(ENO) level responded the earliest to treatment and withdrawal of inhaled corticosteroids, whereas changes in EBC markers were delayed but more sustained.
呼出一氧化氮（F(ENO)）和呼出气冷凝液（EBC）是直接测量气道炎症的非侵入性标志物，可能有助于评估哮喘控制情况及对治疗的反应。
研究吸入性糖皮质激素对F(ENO)和EBC标志物的时间依赖性影响，并同时观察肺功能和支气管高反应性。
11名未使用过类固醇的轻至中度持续性哮喘成年患者接受糠酸莫米松干粉吸入器治疗，剂量为400μg/d，持续8周，随后有4周的洗脱期。分析并比较治疗前、治疗期间及治疗后的第1秒用力呼气容积（FEV1）、使FEV1下降20%时的乙酰甲胆碱浓度（PC20）、F(ENO)、EBC的pH值及EBC亚硝酸盐水平。
到第8周时，平均（SEM）FEV1从3.01（0.13）L（预计值的82%）增至3.24（0.18）L（预计值的87%）（P < 0.05）。到治疗第8周时，PC20水平从1.28（0.31）mg/mL增至2.99（0.51）mg/mL（P < 0.05），在洗脱期第4周时仍保持相对稳定（P < 0.05）。到治疗第1周时，F(ENO)水平从31.1（4.1）ppb降至20.6（4.5）ppb（P < 0.01），在治疗第8周时一直较低（P < 0.01），然后在洗脱期第1周时又趋向于基线水平（P < 0.01）。到治疗第4周时，EBC的pH值中位数从7.81（四分位间距，7.49 - 8.09）增至8.02（四分位间距，7.87 - 8.12），但未达到统计学显著性。到治疗第8周时，EBC亚硝酸盐水平从17.6（1.6）μM降至9.3（0.9）μM（P < 0.01），在整个洗脱期第4周时一直较低（P < 0.05）。F(ENO)与PC20之间存在负相关（Spearman等级相关系数 = -0.50，P < 0.001）。
F(ENO)水平对吸入性糖皮质激素治疗及撤药的反应最早，而EBC标志物的变化虽延迟但更持久。
