Table 2.
Δ (95% CI)* | P-value | |
---|---|---|
Spirometry | ||
FEV1, ml | -32 (-61 to -4) | 0.03 |
FVC, ml | -105 (-160 to -52) | <0.001 |
FEV1/FVC ratio | +0.2% (-0.3% to +0.7%) | 0.47 |
Total Lung Capacity, ml | -64 (-154 to +26) | 0.16 |
Transfer Factor (TLco), mmol/min/kpa | -0.1 (-0.2 to -0.01) | 0.03 |
CT densitometry | ||
Adjusted Lung Density† | -0.24 (-1.1 to +0.6) | 0.58 |
Resting O2 saturation (room air) | -0.2% (-0.3% to -0.03%) | 0.02 |
Incremental Shuttle Walk Test | ||
Distance Walked, meters | -12 (-22 to -2) | 0.02 |
All analyses controlled for age, gender, race-ethnicity, leukocyte count, and tobacco pack-year history. Analysis of total lung capacity also controlled for method of lung capacity assessment (box plethysmography vs helium dilution).
*Change (Δ) associated cross-sectionally with a 25th - 75th percentile interquartile range higher level of MMP-9.
†Measured in Hounsfield Units at the 15th percentile.