Waheed Zeeshan, Irfan Muhammad, Haque Ahmed Suleman, Siddiqui Najmul Hasan, Awan Safia, Syed Beenish, Khan Javaid Ahmed
Section of Pulmonary & Critical Care Medicine, Department of Medicine, The Aga Khan University Hospital, Karachi, Pakistan.
J Pak Med Assoc. 2011 Dec;61(12):1172-5.
To assess the Pre-bronchodilator criteria and the Post-bronchodilator criteria of FEV1/FVC ratio in diagnosing Airflow obstruction.
An observational study was conducted from 1988 to 2006 at the Aga Khan University Hospital Patients referred to the pulmonary function test laboratory for spirometry with bronchodilator reversibility at the hospital during the above said period were enrolled. Forced spirometry was performed according to ATS guidelines. All patients who had pre-bronchodilator criteria of airflow obstruction were analyzed and compared with the post bronchodilator criteria.
A total of 4222 individuals underwent spirometry out of which 4072 individuals were studied. Using the pre bronchodilator criteria, 1375 (34%) patients had airflow obstruction. Applying the post bronchodilator criteria on the same patients, 1098 (27%) had evidence of airway obstruction. Out of these 1375 patients who had airflow obstruction by using pre-bronchodilator criteria, 277 (20%) patients had no airflow obstruction by using the post bronchodilator criteria. Out of these 277 patients, 52% had significant airways reversibility as evidenced by >12% increase in their FEV1 pre and post bronchodilator.
Pre bronchodilator criteria for detection of airflow obstruction overestimate the diagnosis of airflow obstruction and by using post bronchodilator criteria for airway obstruction on spirometry, decreases this over diagnosis of the condition
评估用于诊断气流受限的支气管扩张剂使用前FEV1/FVC比值标准和支气管扩张剂使用后标准。
1988年至2006年在阿迦汗大学医院进行了一项观察性研究。纳入在此期间转诊至医院肺功能测试实验室进行肺活量测定及支气管扩张剂可逆性检测的患者。根据美国胸科学会（ATS）指南进行用力肺活量测定。对所有符合支气管扩张剂使用前气流受限标准的患者进行分析，并与支气管扩张剂使用后标准进行比较。
共有4222人接受了肺活量测定，其中4072人被纳入研究。按照支气管扩张剂使用前标准，1375名（34%）患者存在气流受限。对同一批患者应用支气管扩张剂使用后标准，1098名（27%）有气道阻塞证据。在这1375名按照支气管扩张剂使用前标准存在气流受限的患者中，277名（20%）患者按照支气管扩张剂使用后标准不存在气流受限。在这277名患者中，52%表现出显著的气道可逆性，即支气管扩张剂使用前后FEV1增加>12%。
支气管扩张剂使用前气流受限检测标准高估了气流受限的诊断，而在肺活量测定中使用支气管扩张剂使用后气道阻塞标准可减少对该疾病的过度诊断。
