Characteristics of subjects of the British Regional Heart Study followed-up for 20 years from baseline in 1978–1980
| Baseline examination | 20-year follow-up | |
| Mean age (SD) | 50 (6) | 68 (6) |
| Mean FEV1 in litres (SD) | 3.3 (0.7) | 2.6 (0.7) |
| Mean FVC in litres (SD) | 4.4 (0.7) | 3.4 (0.8) |
| Mean BMI kg/m2 (SD) | 25 (3) | 27 (4) |
| Smoking status | ||
| Current smokers n (%) | 2998 (41%) | 509 (13%) |
| Ex-smokers n (%) | 2610 (36%) | 2362 (58%) |
| Never smokers n (%) | 1767 (24%) | 1204 (30%) |
| Pack years at baseline—median (IQR) | 46 (3, 100) | – |
| Physical activity | ||
| Inactive/occasional n (%) | 2921 (40%) | 1357 (34%) |
| Light n (%) | 1705 (23%) | 739 (19%) |
| Moderate n (%) | 1162 (16%) | 569 (14%) |
| Moderate-vigorous n (%) | 1087 (15%) | 673 (17%) |
| Vigorous n (%) | 500 (7%) | 593 (15%) |
| History of bronchitis at baseline n (%) | 1315 (18%) | – |
| History of asthma at baseline n (%) | 274 (4%) | – |
| Mean decline in FEV1 (SD) over 20 years | −0.86 (0.5) | |
| Mean decline in FVC (SD) over 20 years | −1.13 (0.7) | |