From the Guidelines
Spirometry is crucial for diagnosing COPD, and the key diagnostic criterion is a post-bronchodilator FEV1/FVC ratio less than 0.70, indicating airflow obstruction, as recommended by the GOLD Science Committee in 2025 1. The diagnosis of COPD requires the presence of persistent airflow limitation, which can be confirmed by spirometry. The GOLD report states that a post-bronchodilator FEV1/FVC ratio less than 0.70 is essential for diagnosing COPD 1. This criterion was established in the first GOLD report in 2001 and has been maintained in the 2025 report 1. Some key points to consider when interpreting spirometry results for COPD diagnosis include:
- The use of post-bronchodilator measurements to confirm the presence of persistent airflow obstruction 1
- The importance of considering clinical evaluation and spirometry together to reduce the potential for overdiagnosis and overtreatment 1
- The need for regular spirometry monitoring to track disease progression and treatment response 1 The GOLD Science Committee has re-evaluated the evidence and rationale for using pre- or post-bronchodilator spirometry for the diagnosis of COPD, and the 2025 report maintains the recommendation for using a post-bronchodilator FEV1/FVC ratio less than 0.70 as the key diagnostic criterion 1. In clinical practice, spirometry is underutilized for diagnosing COPD, with studies showing that it has not been performed in 40-50% of patients diagnosed with COPD 1. Therefore, it is essential to encourage more widespread use of spirometry in clinical practice to improve the accuracy of COPD diagnosis and treatment.
From the Research
COPD Diagnosis and Treatment
- COPD is characterized by airflow limitation that is not fully reversible, and spirometry is recommended to determine the presence of airflow obstruction in patients with respiratory symptoms and risk factors 2.
- The use of spirometry in the diagnosis of COPD is crucial, as history and physical examination alone are neither sensitive nor specific for diagnosing COPD 2.
- Treatment guidelines recommend the use of inhaled long-acting bronchodilators to alleviate symptoms and reduce the risk of exacerbations in patients with moderate-to-very-severe COPD 3.
Spirometry in COPD Management
- Spirometry has an impact on COPD management, and its use can help improve the quality of care for patients with COPD 2.
- Barriers to the use of spirometry exist at the patient, provider, and health system level, and innovative quality improvement approaches are needed to increase its use in COPD diagnosis 2.
- Spirometry can help assess the severity of COPD and monitor the response to treatment, including the use of bronchodilators such as tiotropium and salmeterol 4, 5, 6.
Comparison of Tiotropium and Salmeterol
- Tiotropium has been shown to be more effective than salmeterol in preventing exacerbations of COPD, with a 17% reduction in risk 3.
- Tiotropium has also been shown to be superior to salmeterol in improving lung function, as measured by FEV1, and in reducing the need for rescue medication 4, 5, 6.
- The combination of tiotropium and salmeterol has been shown to provide clinically meaningful improvements in airflow obstruction and dyspnea, as well as a reduction in reliever medication 5.