Table 3.
Parameters | No PSE (N=2333) |
Mixed PSE (N=214) |
Pure PSE (N=86) |
P Value*1,2 | |
---|---|---|---|---|---|
All three groups |
Pure PSE vs. No PSE |
||||
FEV1 — % of predicted value*3 | 98.7 ± 14.4 (N=2307) |
91.6 ± 18.8 (N=185) |
90.2 ± 16.7 (N=75) |
<0.001 | 0.15 |
FVC — % of predicted value*3 | 101.9 ± 13.1 (N=2307) |
101.7 ± 15.1 (N=185) |
98.5 ± 14.0 (N=75) |
0.80 | 0.69 |
FEV1 / FVC — % of predicted value*3 | 96.4 ± 8.2 (N=2308) |
89.5 ± 12.2 (N=185) |
91.1 ± 10.6 (N=75) |
<0.001 | 0.002 |
Spirometric restriction — no./total no. (%)*4 | 70 (3) (N=2207) |
5 (3) (N=185) |
4 (5) (N=75) |
0.51 | 0.28 |
Airflow obstruction — no./total no. (%)*5 | 85 (4) (N=2207) |
26 (14) (N=185) |
12 (16) (N=75) |
<0.001 | <0.001 |
DLCO — % of predicted value*6 | 97.9 ± 15.1 (N=2049) |
87.4 ± 17.7 (N=152) |
87.0 ± 14.0 (N=61) |
<0.001 | 0.002 |
Total lung capacity — % of predicted value*7 | 83.6 ± 14.9 (N=2154) |
89.6 ± 16.6 (N=196) |
89.5 ± 14.5 (N=78) |
0.09 | 0.08 |
Plus-minus values are mean ± standard deviation.
PSE: paraseptal emphysema, FEV: forced expiratory volume, FEV1: forced expiratory volume in 1 second, FVC: forced vital capacity, DLCO: diffusing capacity of the lung for carbon monoxide.
P values for the comparison among all three groups and for the comparison between participants with and without pure paraseptal emphysema were calculated with the use of linear mixed effect models to account for familial relationships in the Framingham Heart Study, as described previously [21].
All the P values for variables of pulmonary function test were adjusted by age, smoking status (current, former or never), and pack-years.
Predicted values for FEV1 and FVC are derived from Hankinson et al [30].
Spirometric restriction is defined as an FVC of less than 80% of the predicted value with an FEV1/ FVC ratio that is more than the lower limit of the normal range [30].
Airflow obstruction is defined as an FEV1 and an FEV1/ FVC ratio that are both less than the lower limit of the normal range [30].
Predicted values for DLCO are derived from Miller et al [31].
Quantitative values for total lung capacity were calculated using Airway Inspector (www.airwayinspector.org). Predicted values for total lung capacity are derived from the guidelines of the American Thoracic Society and European Respiratory Society [32].