Joyce D P, Chapman K R, Kesten S
Asthma Centre of The Toronto Hospital, University of Ontario, Canada.
Chest. 1996 Mar;109(3):697-701. doi: 10.1378/chest.109.3.697.
Previous research indicates that asthma has been underdiagnosed. However, we suspect that recent widespread attention to the underdiagnosis of asthma has led to an overdiagnosis of asthma in some settings. We therefore sought to examine prior diagnosis and treatment of patients referred to our facility and subsequently found to have no objective evidence of variable airflow limitation.
Retrospective chart review.
Hospital-based asthma center.
A referred sample of 263 patients in whom a methacholine challenge (MCC) was conducted after evaluation by our pulmonologists; complete medical histories were available.
Prior respiratory diagnoses, duration of treatment with asthma medications, and diagnosis following assessment by our pulmonologists in 175 patients with a provocative concentration of the substance causing a 20% fall in FEV1 (PC20) greater than 8.0 mg/mL and 88 with a PC20 of 8.0 mg/mL or less.
Of those with a PC20 greater than 8 mg/mL, a diagnosis of asthma or possible asthma prior to the challenge study was recorded by their primary care physician in 129 patients (74%). One hundred sixty of 172 patients (88%) with a PC20 greater than 8 mg/mL were diagnosed as not having asthma by our pulmonologists; 109 of 172 patients (62%) had been previously treated with asthma medication(s). The mean duration of asthma treatment was 25.9+/- 56.3 months, and there was no significant difference in the duration of treatment between this group and those who had a PC20 of 8 mg/mL or less. Most of those treated received inhaled beta2-agonists and inhaled corticosteroids. Approximately 61% received two or more classes of medications.
The misdiagnosis of asthma occurs commonly in the referral practice of a tertiary care asthma center. The more frequent use of objective pulmonary function testing in primary practice might reduce the problem of delayed diagnosis and inappropriate therapy for respiratory symptoms.
先前的研究表明哮喘存在诊断不足的情况。然而，我们怀疑近期对哮喘诊断不足的广泛关注在某些情况下导致了哮喘的过度诊断。因此，我们试图检查转诊至我们机构的患者的既往诊断和治疗情况，这些患者随后被发现没有气流受限变异性的客观证据。
回顾性病历审查。
医院哮喘中心。
263例经我们的肺科医生评估后进行了乙酰甲胆碱激发试验（MCC）的转诊患者样本；可获取完整的病史。
175例激发物质浓度导致第一秒用力呼气容积（FEV1）下降20%时的激发浓度（PC20）大于8.0mg/mL的患者以及88例PC20为8.0mg/mL或更低的患者的既往呼吸诊断、哮喘药物治疗持续时间以及经我们的肺科医生评估后的诊断。
在PC20大于8mg/mL的患者中，其初级保健医生在激发试验研究前记录为哮喘或可能哮喘诊断的有129例（74%）。在172例PC20大于8mg/mL的患者中，有160例（88%）被我们的肺科医生诊断为无哮喘；172例患者中有109例（62%）曾接受过哮喘药物治疗。哮喘治疗的平均持续时间为25.9±56.3个月，该组与PC20为8mg/mL或更低的组之间的治疗持续时间无显著差异。大多数接受治疗的患者使用了吸入性β2激动剂和吸入性糖皮质激素。约61%的患者接受了两类或更多类药物治疗。
哮喘的误诊在三级医疗哮喘中心的转诊实践中很常见。在初级医疗实践中更频繁地使用客观肺功能测试可能会减少呼吸症状延迟诊断和不适当治疗的问题。
