General characteristics in the Rotterdam Study (RS) population (the “discovery panel”) and the Framingham Heart Study (FHS) population (the “replication” panel)
| Characteristic | Study | |
| RS (n=659) | FHS (n=2114) | |
| Age years | 67.4±5.90 | 65.6±8.38 |
| Female sex | 369 (56) | 1159 (55) |
| Current smokers | 70 (11) | 151 (7) |
| Ex-smokers | 379 (58) | 1186 (56) |
| Weight kg | 79.9±13.94 | 79.5±17.83 |
| Height cm | 169.8±9.16 | 167.3±9.54 |
| FEV1 L | 2.72 (0.71) | 2.68 (0.75) |
| % predicted FEV1 | 102.85 (22.82) | 97.94 (16.94) |
| FVC L | 3.56 (0.90) | 3.68 (0.98) |
| % predicted FVC | 108.93 (16.92) | 101.39 (15.09) |
| FEV1/FVC % | 76.65 (7.33) | 72.89 (6.86) |
| DLCO# mmol·min−1·kPa−1 | 7.81±1.64 | 7.47±2.13 |
| DLCO/VA# mmol·min−1·kPa−1·VA−1 | 1.52±0.23 | 1.42±0.23 |
Data are presented as mean±sd (for continuous variables) or n (%) (for dichotomous variables). FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; DLCO: diffusing capacity of the lung for carbon monoxide; VA: alveolar volume; sd: standard deviation. #: DLCO was corrected for haemoglobin levels in the RS. Interpretable spirometry was available in the RS (n=625) and FHS (n=2114).