Table 2.
Characteristics and lung function measures in individuals with and without restrictive lung function defined by TLC < LLN
| Parameter | Restrictive lung function, n = 32 | No restrictive lung function, n = 575 | p |
|---|---|---|---|
| Age | 51.4 ± 11.6 | 48.4 ± 12.6 | 0.187 |
| Female sex, n (%) | 17 (53.1) | 279 (48.5) | 0.612 |
| Height | 168.5 ± 8.8 | 170.8 ± 9.1 | 0.166 |
| Body mass index (kg/m2) | 26.1 ± 4.2 | 25.6 ± 3.5 | 0.406 |
| Never‐smoker, n (%) | 15 (46.9) | 254 (44.2) | 0.756 |
| Ex‐smoker,a n (%) | 11 (34.4) | 168 (29.2) | 0.538 |
| Smoker, n (%) | 6 (18.8) | 153 (26.6) | 0.323 |
| PD asthma | 6 (18.8) | 55 (9.6) | 0.093 |
| PD emphysema or chronic bronchitis | 2 (6.3%) | 31 (5.4%) | 0.326 |
| TLC% of predicted | 76.7 ± 5.2 | 100.5 ± 10.6 | <0.001 |
| TLC Z‐score | −2.1 ± 0.5 | 0.03 ± 0.9 | <0.001 |
| FEV1% of predicted | 77.4 ± 13.3 | 93.5 ± 15.3 | <0.001 |
| FEV1 Z‐score | −1.6 ± 0.9 | −0.4 ± 1.1 | <0.001 |
| FVC% of predicted | 76.3 ± 10.7 | 95.8 ± 12.7 | <0.001 |
| FVC Z‐score | −1.7 ± 0.8 | −0.3 ± 0.9 | <0.001 |
| FEV1/FVC | 0.8 ± 0.02 | 0.8 ± 0.02 | 0.338 |
| FEV1/FVC Z‐score | 0.1 ± 0.8 | −0.3 ± 1.0 | 0.020 |
Note: Results presented as number and proportion (%) of individuals and/or mean ± SD unless otherwise stated.
Abbreviations: FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; LLN, lower limit of normal; PD, physician diagnosis; SD, standard deviation; TLC, total lung capacity.
a
Ex‐smoker = smoked for at least 1 year but not during the last 12 months.