Baseline cohort characteristics
| Parameter | Study population (n=603) | First quartile† (n=151) | Second quartile (n=150) | Third quartile (n=147) | Fourth quartile (n=154) |
| Age (years) | 71±9 | 72±1 | 71±1 | 70±1 | 69±1 |
| Sex (male) | 460 (76%) | 121 (80%) | 122 (81%) | 105 (71%) | 111 (72%) |
| Ever smoker | 422 (70%) | 104 (69%) | 109 (73%) | 101 (69%) | 108 (70%) |
| Mean FVC, % predicted | 69.2±17.7 | 71.4±18.2 | 70.6±17.9 | 68.4±16.3 | 66.3±17.8 |
| Mean DLCO, % predicted | 46.3±17.4 | 51.0±17.9 | 48.7±17.6 | 41.7±15.0 | 43.6±17.3 |
| Received lung transplant | 71 (12%) | 19 (12%) | 15 (10%) | 20 (14%) | 17 (11%) |
| Received antifibrotic treatment* | 216 (36%) | 68 (45%) | 51 (34%) | 56 (38%) | 39 (25%) |
| No of deaths | 317 (53%) | 81 (54%) | 82 (55%) | 74 (50%) | 80 (52%) |
| Median (IQR) follow-up (years) | 2.2 (1.9–2.5) | 1.9 (1.5–2.5) | 2.4 (1.7–2.8) | 2.4 (2.1–3.7) | 1.9 (1.4–3.0) |
Data are presented as mean±SD or no (%) unless otherwise indicated.
First quartile includes patients at lowest relative disadvantage, and fourth quartile at greatest relative disadvantage.
*Antifibrotic treatment refers to IPF-specific medications pirfenidone or nintedanib in patients who had ongoing follow-up subsequent to 1 November 2014.
†Results presented per quartile for patients with complete exposure data
DLCO, diffusion capacity of the lung for carbon monoxide; FVC, forced vital capacity; IPF, idiopathic pulmonary fibrosis.