Salome C M, Leuppi J D, Freed R, Marks G B
Woolcock Institute of Medical Research (formerly known as Institute of Respiratory Medicine), University of Sydney, NSW 2006, Australia.
Thorax. 2003 Dec;58(12):1042-7. doi: 10.1136/thorax.58.12.1042.
The perception of airway narrowing is reduced in subjects with severe asthma and may be related to the severity of airway inflammation. A study was undertaken to determine if the perception of airway narrowing changes during the reduction of inhaled corticosteroid (ICS) dose or during an asthma exacerbation.
Forty two asthmatic subjects with well controlled asthma had their daily ICS dose halved every 2 months until they were weaned off ICS or they developed an exacerbation. Perception was measured at baseline and at monthly intervals during bronchial challenge with mannitol as the slope and intercept of the regression of the Borg score and percentage fall in forced expiratory volume in 1 second (FEV(1)), and as the Borg score at 20% fall in FEV(1) (PS(20)FEV(1)). Sputum was collected for measurement of inflammatory cell numbers.
In 33 subjects who successfully halved their ICS dose without exacerbation there were significant reductions in slope (p = 0.01), intercept (p = 0.01), and PS(20)FEV(1) (p = 0.003). Sputum eosinophils and airway hyperresponsiveness increased significantly but, in 14 subjects from whom sputum was obtained, changes in eosinophils were not correlated with changes in perception. Change in airway hyperresponsiveness correlated with change in PS(20)FEV(1) (r = -0.40, p = 0.025). In 27 subjects who developed an exacerbation, slope decreased (p = 0.02) and intercept increased (p = 0.01) compared with the visit before the exacerbation. Changes in intercept correlated with changes in resting FEV(1) (r = -0.57, p = 0.002).
Perception of airway narrowing decreases during ICS dose reduction and decreases further during a mild asthma exacerbation. These changes are related to concurrent changes in airway hyperresponsiveness and resting lung function. The effect of changes in airway inflammation on perception is unclear.
重度哮喘患者对气道狭窄的感知降低，这可能与气道炎症的严重程度有关。开展了一项研究，以确定在吸入性糖皮质激素（ICS）剂量减少期间或哮喘发作期间气道狭窄的感知是否会发生变化。
42名哮喘控制良好的哮喘患者每2个月将其每日ICS剂量减半，直至停用ICS或病情加重。在基线以及使用甘露醇进行支气管激发试验期间每月测量一次感知，测量指标为Borg评分与1秒用力呼气容积（FEV₁）下降百分比的回归斜率和截距，以及FEV₁下降20%时的Borg评分（PS₂₀FEV₁）。收集痰液以测量炎症细胞数量。
在33名成功将ICS剂量减半且未加重病情的受试者中，斜率（p = 0.01）、截距（p = 0.01）和PS₂₀FEV₁（p = 0.003）均显著降低。痰液嗜酸性粒细胞和气道高反应性显著增加，但在14名获取痰液的受试者中，嗜酸性粒细胞的变化与感知变化无关。气道高反应性的变化与PS₂₀FEV₁的变化相关（r = -0.40，p = 0.025）。在27名病情加重的受试者中，与加重前的访视相比，斜率降低（p = 0.02），截距增加（p = 0.01）。截距的变化与静息FEV₁的变化相关（r = -0.57，p = 0.002）。
在ICS剂量减少期间，气道狭窄的感知降低，在轻度哮喘发作期间进一步降低。这些变化与气道高反应性和静息肺功能的同时变化有关。气道炎症变化对感知的影响尚不清楚。
