Belda J, Giner J, Casan P, Sanchis J
Hospital de la Santa Creu i Sant Pau, Barcelona, Catalunya, Spain.
Chest. 2001 Apr;119(4):1011-7. doi: 10.1378/chest.119.4.1011.
To determine the time to exacerbation and probability of a mild exacerbation of asthma, and the impact of eosinophilic inflammation on these parameters in patients with stable, well-controlled asthma.
A cohort of 31 patients with stable, well-controlled asthma receiving inhaled steroid treatment regularly were followed up for 1 year or until a mild exacerbation occurred. Mild exacerbation was defined as symptoms of asthma lasting > 48 h with a fall in peak expiratory flow > 20%. FEV(1), provocative concentration of methacholine causing a 20% fall in FEV(1), eosinophil count, and eosinophilic cationic protein (ECP) levels in blood and in sputum were measured at the first visit and every 2 months.
At baseline, the mean (SD) eosinophil count was 0.39 x 10(9)/L (0.21 x 10(9)/L) in blood and 13% (14%) in sputum; ECP was 30 microg/L (28 microg/L) in blood and 75 microg/L (85 microg/L) in sputum. Thirteen subjects experienced a mild exacerbation during the 1-year follow-up period. The mean time to mild exacerbation was 293 days (95% confidence interval [CI], 248 to 337 days), and the cumulative probability of not experiencing a mild exacerbation in 1 year was 49% (95% CI, 39 to 59%). An increased risk of mild exacerbation was associated with blood eosinophil count > 0.4 x 10(9)/L (relative risk 4.5; 95% CI of relative risk, 1.8 to 38.0), blood ECP > 20 microg/L (relative risk, 2.1; 95% CI of relative risk, 1.0 to 9.2), and sputum ECP > 40 microg/L (relative risk, 2.5; 95% CI of relative risk, 1.2 to 11.2), but was unassociated with other variables.
Patient with stable, well-controlled asthma are at risk of mild exacerbation during 1 year of follow-up despite regular inhaled steroid treatment. Eosinophilic inflammation expressed as eosinophil count and ECP is associated with higher risk of mild exacerbation.
确定哮喘轻度加重的时间和概率，以及嗜酸性粒细胞炎症对稳定、控制良好的哮喘患者这些参数的影响。
对31例规律接受吸入性糖皮质激素治疗的稳定、控制良好的哮喘患者进行为期1年的随访，或直至发生轻度加重。轻度加重定义为哮喘症状持续超过48小时，且呼气峰值流速下降超过20%。在首次就诊时及每2个月测量1次第1秒用力呼气容积（FEV₁）、使FEV₁下降20%的乙酰甲胆碱激发浓度、血液及痰液中的嗜酸性粒细胞计数和嗜酸性粒细胞阳离子蛋白（ECP）水平。
基线时，血液中嗜酸性粒细胞计数的均值（标准差）为0.39×10⁹/L（0.21×10⁹/L），痰液中为13%（14%）；血液中ECP为30μg/L（28μg/L），痰液中为75μg/L（85μg/L）。13例受试者在1年随访期间发生了轻度加重。轻度加重的平均时间为293天（95%置信区间[CI]，248至337天），1年内未发生轻度加重的累积概率为49%（95%CI，39至59%）。血液嗜酸性粒细胞计数>0.4×10⁹/L（相对危险度4.5；相对危险度的95%CI，1.8至38.0）、血液ECP>20μg/L（相对危险度，2.1；相对危险度的95%CI，1.0至9.2）和痰液ECP>40μg/L（相对危险度，2.5；相对危险度的95%CI，1.2至11.2）与轻度加重风险增加相关，但与其他变量无关。
尽管规律接受吸入性糖皮质激素治疗，但稳定、控制良好的哮喘患者在1年随访期间仍有发生轻度加重的风险。以嗜酸性粒细胞计数和ECP表示的嗜酸性粒细胞炎症与轻度加重的较高风险相关。
