Figure 5. Kaplan-Meier plots for the probability of remaining free of AECOPD.
(A) In SPIROMICS, the median time-to-first event was 10 months shorter in individuals with elevated MMP-9 compared with those without MMP-9 elevation (21.7 months [95% CI, 17.5–25.9] versus 31.7 months [95% CI, 27.2–36.2], P = 0.015). (B) In COPDGene, the median time-to-first AECOPD was also shorter among the elevated MMP-9 group (14 months [95% CI, 9.4–18.6] versus 21 months [95% CI, 15–27], P = 0.065). AECOPD, acute exacerbation of chronic obstructive pulmonary disease; MMP, matrix metalloprotease.