哮喘严重程度定量指标的临床意义变化。

Clinically meaningful changes in quantitative measures of asthma severity.

作者信息

Karras D J, Sammon M E, Terregino C A, Lopez B L, Griswold S K, Arnold G K

机构信息

Division of Emergency Medicine, Temple University School of Medicine, Philadelphia, PA 19140, USA.

出版信息

Acad Emerg Med. 2000 Apr;7(4):327-34. doi: 10.1111/j.1553-2712.2000.tb02231.x.

DOI:10.1111/j.1553-2712.2000.tb02231.x

PMID:10805619

Abstract

OBJECTIVE

To determine minimum clinically meaningful improvements in peak expiratory flow rate (PEFR) and dyspnea visual analog score (VAS) in patients with acute asthma exacerbation.

METHODS

Patients presenting to the emergency department (ED) with acute asthma exacerbation were eligible. The PEFR and VAS were assessed at presentation and after initial asthma therapy. During reassessment, subjects were asked to describe their asthma symptoms as "much better," "a little better," "no change," "a little worse," or "much worse." Correspondence between self-reported improvement and changes in PEFR and VAS was assessed. The "minimum clinically significant change" in either index was defined as the difference between pre- and posttreatment measures in subjects reporting their symptoms "a little better."

RESULTS

One hundred fifty-six subjects were included. Asthma symptoms were "much better" in 99 (64%), "a little better" in 41 (26%), and "unimproved" (composed of patients describing symptoms as "no change," "a little worse," or "much worse") in 16 (10%). The mean VAS change among the "a little better" subjects was 2.2 cm (95% CI = 1.1 to 3.4), significantly greater than the -0.4 cm (95% CI = -2.1 to 1.4) change in the "unimproved" subjects. The mean change in percent predicted PEFR among the "a little better" subjects was 11.9 (95% CI = 7.3 to 16.1), not statistically different from the change of 6.1 (95% CI = 1.1 to 11.3) in the "no change" subjects. The "much better" group showed significantly greater changes in both measures than either of the other groups. A VAS change of > or =0.5 cm reliably discriminated between subjects with and without symptom improvement.

CONCLUSIONS

Improvements in VAS of 2.2 cm and in predicted PEFR of about 12 percentage points are minimal clinically significant improvements during ED asthma therapy. The dyspnea VAS is valid in assessing symptomatic changes and may detect small subjective improvements better than the PEFR.

摘要

目的

确定急性哮喘加重患者呼气峰值流速（PEFR）和呼吸困难视觉模拟评分（VAS）的最小临床有意义改善。

方法

符合条件的患者为因急性哮喘加重而到急诊科就诊者。在就诊时和初始哮喘治疗后评估PEFR和VAS。在重新评估期间，要求受试者将其哮喘症状描述为“好多了”“稍好一点”“无变化”“稍差一点”或“差得多”。评估自我报告的改善与PEFR和VAS变化之间的对应关系。任一指标的“最小临床显著变化”定义为报告症状“稍好一点”的受试者治疗前和治疗后测量值之间的差异。

结果

纳入156名受试者。哮喘症状“好多了”的有99人（64%），“稍好一点”的有41人（26%），“未改善”（包括描述症状为“无变化”“稍差一点”或“差得多”的患者）的有16人（10%）。“稍好一点”组受试者的VAS平均变化为2.2厘米（95%可信区间=1.1至3.4），显著大于“未改善”组受试者-0.4厘米（95%可信区间=-2.1至1.4）的变化。“稍好一点”组受试者预计PEFR的平均变化百分比为11.9（95%可信区间=7.3至16.1），与“无变化”组6.1（95%可信区间=1.1至11.3）的变化无统计学差异。“好多了”组在这两项测量中的变化均显著大于其他两组中的任何一组。VAS变化≥0.5厘米可可靠地区分有症状改善和无症状改善的受试者。