| Characteristic | Rapid decliners | Slow decliners | p-value |
| Participants | 98 | 98 | |
| Males | 62 (63) | 60 (61) | 0.77 |
| Caucasians | 86 (88) | 97 (99) | 0.002 |
| Age yrs | 53.2±6.9 | 52.2±6.6 | 0.31 |
| Smoking intensity reported at Y5 cigarettes·day−1 | 25.1±12.6 | 21.5±11.6 | 0.04 |
| Y5 FEV1 L | 2.35±0.63 | 2.49±0.65 | 0.09 |
| Y5 FEV1 % pred | 71.0±12.1 | 73.2±11.5 | 0.15 |
| Y5 FVC L | 4.10±1.02 | 3.94±0.99 | 0.23 |
| Y5 FVC % pred | 98.6±13.7 | 92.1±11.4 | <0.001 |
| Time between Y5 to LT spirometry visits yrs | 6.0±0.64 | 5.8±0.66 | 0.06 |
| LT FEV1 L | 1.44±0.52 | 2.49±0.66 | <0.001 |
| LT FEV1 % pred | 45.2±13.3 | 77.2±11.6 | <0.001 |
| LT FVC L | 3.31±1.01 | 3.92±1.05 | <0.001 |
| LT FVC % pred | 81.7±17.0 | 94.2±12.6 | <0.001 |
Data are presented as n, n (%) or mean±sd, unless otherwise stated. All participants were continuous smokers from the first visit in the main Lung Health Study trial to the long-term follow-up visit (LT). Y5: year 5 visit; FEV1: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity.