Mean (SD) FEV1 % predicted and FEV1/FVC of index and non-index cases stratified by age at entry
| Index cases | Non-index cases | p value (t test) | |
|---|---|---|---|
| All age groups | n = 27 | n = 40 | |
| FEV1 (% predicted) | 54 (25) | 100 (21) | <0.001 |
| FEV1/FVC | 0.57 (0.18) | 0.79 (0.13) | <0.001 |
| N (%) with FEV1 % pred ⩽70% | 20 (74%) | 3 (8%) | <0.001 |
| Age at entry <50 years | n = 8 | n = 26 | |
| FEV1 (% predicted) | 56 (37) | 100 (19) | <0.001 |
| FEV1/FVC | 0.53 (0.20) | 0.80 (0.12) | <0.001 |
| N (%) with FEV1 % pred ⩽70% | 4 (50%) | 2 (8%) | <0.001 |
| Age at entry ⩾50 years | n = 19 | n = 14 | |
| FEV1 (% predicted) | 50 (20) | 101 (24) | <0.001 |
| FEV1/FVC | 0.58 (0.17) | 0.78 (0.14) | <0.001 |
| N (%) with FEV1 % pred ⩽70% | 16 (84%) | 1 (7%) | <0.001 |