Table 3.
Associations between 0.1-mm increase in Pi10 and changes in total lung capacity and forced vital capacity in participants with interstitial lung abnormalities and idiopathic pulmonary fibrosis
| COPDGene |
ECLIPSE |
Framingham Heart Study |
IPF Cohort |
|||||
|---|---|---|---|---|---|---|---|---|
| Analysis | Mean Difference in Percent Predicted Volume (95% CI) | P Value | Mean Difference in Percent Predicted Volume (95% CI) | P Value | Mean Difference in Percent Predicted Volume (95% CI) | P Value | Mean Difference in Percent Predicted Volume (95% CI) | P Value |
| TLC unadjusted | −3.4 (−4.2 to −2.6) | <0.001 | −2.7 (−5.2 to −0.2) | 0.04 | −1.5 (−2.8 to −0.2) | 0.03 | 0.07 (−0.7 to 0.8) | 0.88 |
| TLC adjusted* | −4.1 (−4.9 to −3.4) | <0.001 | −2.1 (−4.8 to 0.5) | 0.11 | −1.3 (−2.5 to −0.1) | 0.03 | −0.2 (−1.3 to 0.9) | 0.67 |
| FVC unadjusted | −4.3 (−5.1 to −3.4) | <0.001 | −2.3 (−3.9 to −0.8) | 0.004 | −0.4 (−1.5 to 0.7) | 0.47 | −0.03 (−1.0 to 1.0) | 0.95 |
| FVC adjusted | −2.2 (−2.8 to −1.5) | <0.001 | −0.9 (−2.6 to 0.7) | 0.25 | −0.08 (−1.2 to 1.1) | 0.89 | −0.3 (−1.6 to 0.9) | 0.59 |
Definition of abbreviations: CI = confidence interval; COPDGene = Genetic Epidemiology of COPD study; ECLIPSE = Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study; FVC = forced vital capacity as a percentage of predicted value; IPF = idiopathic pulmonary fibrosis; Pi10 = square root of the airway wall area of a hypothetical airway with internal perimeter of 10 mm (Mean changes in percent predicted lung volumes are calculated using linear regression models among those with interstitial lung abnormalities and IPF; the associations reflect the correlations between a 0.1-mm increase in Pi10 and the result of measures of lung volumes.); TLC = total lung capacity as a percentage of predicted value.
Adjusted analyses in participants with interstitial lung abnormalities are adjusted for age, sex, pack-years of smoking, current smoking status, body mass index, and Global Initiative for Chronic Obstructive Lung Disease stage (when available). In participants with interstitial lung abnormalities, they are adjusted for age, sex, body mass index, and pack-years of smoking.