A lowered FEV3/FEV6 is associated with an increased risk of COPD and lung attacks in current and former smokers without COPD. This simple, routinely available and reproducible method has the potential to identify early on who are at increased risk for COPD, so that timely treatment is possible.
Early in the course of COPD, the small airways are affected. Traditional spirometric indices may not accurately determine disease activity in the small airways. The question is whether with a ratio between the forced expiratory volume in 3 and 6 seconds (FEV3/FEV6) an airway obstruction can be detected early, which is predictive of the development of respiratory diseases, such as COPD.
This analysis of the SPIROMICS cohort included 832 current and former smokers with post-bronchodilator FEV1/FVC of ≥ 0.7 and an FEV3/FEV6 below the lower limit of normal (LLN) at baseline.
On repeated measurements, the FEV3 a FEV6 good corresponding results. A decreased FEV3/FEV6 was associated with a greater likelihood of severe lung attacks during the first year of follow-up and a shorter time to first lung attack. A low FEV3/FEV6 was also associated with the development of COPD, assessed by spirometry (post-bronchodilator FEV1/FVC of < 0.7) during study follow-up.
A lowered FEV3/FEV6 can identify those at risk for developing COPD and lung attacks. These data therefore indicate that in the studied patient population, in addition to the FEV1 and FVC, other spirometric results should also be established, as these may provide additional clinically relevant insights.
Bron:
Yee N, Markovic D, Buhr RG, et al. Significance of FEV3/FEV6 in Recognition of Early Airway Disease in Smokers at Risk of Development of COPD: Analysis of the SPIROMICS Cohort. Chest. 2022;161:949-59.