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Defining Airflow Obstruction
1Cincinnati Veterans Administration Medical Center, Ohio.
Chronic Obstructive Pulmonary Diseases (Miami, Fla.)
|May 31, 2016
Summary
Current definitions of airflow obstruction using spirometry (FEV1/FVC ratio) rely on normal population data. This study suggests defining obstruction based on COPD patient data for improved diagnostic accuracy.
Area of Science:
- Pulmonary Medicine
- Diagnostic Criteria
- Spirometry
Background:
- Current airflow obstruction diagnosis relies on fixed FEV1/FVC ratios (<70%) or lower limits of normal (LLN) derived from healthy populations.
- This approach may misclassify individuals with chronic obstructive pulmonary disease (COPD).
Purpose of the Study:
- To propose an alternative method for defining airflow obstruction.
- To explore defining airflow obstruction based on FEV1/FVC values within a known COPD patient population.
Main Methods:
- The study critically evaluates the current spirometric definition of airflow obstruction.
- It highlights the lack of established FEV1/FVC distributions for COPD patients.
- It suggests a probabilistic approach to defining airflow obstruction.
Main Results:
- The current spirometric definition of airflow obstruction, based on healthy population data, is questioned.
- There is no established gold standard for FEV1/FVC values in COPD patients.
- A binary (present/absent) definition of airflow obstruction may be insufficient.
Conclusions:
- A shift from a fixed cutoff to a probability-based definition of airflow obstruction is advocated.
- This approach could provide a more accurate likelihood of disease states like COPD.
- Further research is needed to establish FEV1/FVC distributions in COPD populations.
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