LindenSmith Jorin, Morrison Debra, Deveau Carole, Hernandez Paul
Dalhousie University, Halifax, Canada.
Can Respir J. 2004 Mar;11(2):111-6. doi: 10.1155/2004/276493.
Overdiagnosis of asthma may be an emerging problem after years of attention to the rising prevalence and reported underdiagnosis of the disease.
A sample of adult asthmatics from the community was investigated to determine whether they met the current diagnostic criteria for asthma.
Ninety participants were studied from a self-referred sample of physician-labelled, adult asthmatics from the community. The setting was a tertiary care, university-affiliated teaching hospital in Halifax, Nova Scotia. Three diagnostic criteria from the Canadian Thoracic Society Asthma Guidelines were used to demonstrate the presence of asthma: first, positive symptom history, and either, second, reversible airflow obstruction demonstrable on spirometry or documented peak expiratory flow rate diurnal variability, or, third, bronchial hyperreactivity to methacholine.
At the time of the study, 41% of a sample of physician-labelled asthmatics showed no evidence of reversible airflow obstruction and had a negative methacholine challenge. By backward logistical regression analysis, a higher mean number of medications used (P<0.01), a lower forced expiratory volume in 1 s (P<0.05) and using inhaled steroids (P<0.05) were predictive of meeting the diagnostic criteria for asthma. Sixty-two per cent of subjects who did not meet the criteria for asthma were currently taking medications for "asthma". Only 52.2% of the subjects reported ever having undergone pulmonary function testing.
Overdiagnosis of asthma is a potential problem, which may result in unnecessary or inappropriate medication use, increased health care costs and mislabelling of patients. The authors recommend greater use of objective diagnostic tests such as spirometry, peak flow diaries and bronchial provocation to establish a clinical diagnosis of asthma.
在多年关注哮喘患病率上升及报道的诊断不足问题之后，哮喘的过度诊断可能正成为一个新出现的问题。
对来自社区的成年哮喘患者样本进行调查，以确定他们是否符合当前哮喘诊断标准。
对来自社区自我推荐的、经医生诊断为成年哮喘患者的90名参与者进行研究。研究地点是新斯科舍省哈利法克斯市一家三级医疗、大学附属教学医院。采用加拿大胸科学会哮喘指南中的三项诊断标准来证明哮喘的存在：第一，有阳性症状史，第二，肺功能测定显示可逆性气流受限或记录的呼气峰值流速日变异率，或者第三，对乙酰甲胆碱支气管高反应性。
在研究时，经医生诊断为哮喘的样本中41%没有可逆性气流受限的证据且乙酰甲胆碱激发试验阴性。通过向后逻辑回归分析，使用药物的平均数量较多（P<0.01）、第1秒用力呼气量较低（P<0.05）以及使用吸入性类固醇（P<0.05）可预测符合哮喘诊断标准。62%不符合哮喘标准的受试者目前正在服用“哮喘”药物。只有52.2%的受试者报告曾进行过肺功能测试。
哮喘的过度诊断是一个潜在问题，可能导致不必要或不适当的药物使用、医疗保健成本增加以及患者标签错误。作者建议更多地使用客观诊断测试，如肺功能测定、峰值流速日记和支气管激发试验来建立哮喘的临床诊断。
