Interestingly, we found that MMP-2 level at T18 was significantly associated with the severity of airway obstruction (FEV1/FVC, p = 0.02, 95% CI [0.11;0.86] and was lower in GOLD D patients compared to GOLD A patients (7.8 ± 2 105 AU vs 12.8 ± 0.13 105 AU, p = 0.04). The gene discussed is MMP2; the disease is Airway obstruction.