Summary of baseline characteristics for all individuals
| Characteristic | Placebo (n=86) | Co-trimoxazole (n=95) |
|---|---|---|
| Mean/number (SD/%) | Mean/number (SD/%) | |
| Women | 21 (24.4%) | 29 (30.5%) |
| Age (years) | 70.65 (8.56) | 72.38 (8.45) |
| Body mass index (kg/m2) | 28.61 (5.54) | 28.86 (8.03) |
| Smoking history | ||
| Current | 1 (1.2%) | 1 (1.1%) |
| Ex-smoker | 65 (75.6%) | 71 (74.7%) |
| Never | 20 (23.3%) | 23 (24.2%) |
| Clinical diagnosis | ||
| UIP | 81 (94.2%) | 89 (93.7%) |
| NSIP | 5 (5.8%) | 6 (6.3%) |
| Biopsy | ||
| Open lung | 5/15 (5.8%) | 3/14 (3.2%) |
| Video-assisted thoracic surgery | 10/15 (11.6%) | 11/14 (11.6%) |
| Pathological/radiological diagnosis | ||
| Definite IPF (UIP histopathology, honeycombing on HRCT or in report on destroyed HRCT) | 38 | 37 |
| Probable IPF (Fell probability score ≥0.6) | 41 | 46 |
| Probable IPF (all features consistent with UIP except honeycombing on HRCT or in report on destroyed HRCT) | 40 | 46 |
| Time from diagnosis to randomisation (months)* | 31.1 (56.8) | 25.5 (37.1) |
| Diagnosis within 12 months | 21 (24.4%) | 25 (26.3%) |
| Co-existing emphysema | 9 (10.5%) | 6 (6.3%) |
| MRC dyspnoea score | ||
| 2 | 17 (19.8%) | 12 (12.6%) |
| 3 | 28 (32.6%) | 42 (44.2%) |
| 4 | 31 (36.1%) | 31 (32.6%) |
| 5 | 10 (11.6%) | 10 (10.5%) |
| FVC (l) | 2.4 (0.8) | 2.3 (0.9) |
| FVC percent predicted (%) | 71.5 (21.0) | 70.0 (21.5) |
| TLC (l) | 4.2 (1.6) | 3.8 (1.1) |
| TLC percent predicted (%) | 66.3 (22.5) | 61.8 (15.8) |
| Dlco (mmol/min/kPa) | 3.5 (1.9) | 3.2 (1.6) |
| Dlco percent predicted (%) | 39.1 (12.8) | 36.0 (10.0) |
| 6 MW distance (m) | 331.2 (117.6) | 285.6 (96.1) |
| 6 MW desaturation ≥4% | 32/43 (74.4%) | 31/38 (81.6%) |
| SGRQ total (units) | 59.3 (17.5) | 55.7 (17.9) |
| Treatment | ||
| Prednisolone | 52 (60·5%) | 54 (56.8%) |
| <10 mg/day | 11 (12.8%) | 17 (17.9%) |
| 10–20 mg/day | 39 (45.3%) | 36 (37.9%) |
| >20 mg/day | 2 (2.3%) | 1 (1%) |
| Azathioprine | 26 (30.2%) | 28 (29.5%) |
| Mycophenolate mofetil | 3 (3.5%) | 4 (4.2%) |
| Carbocysteine | 2 (2.3%) | 2 (2.1%) |
| Mecysteine | 0 (0.0%) | 1 (1.1%) |
| N-acetylcysteine | 20 (23.3%) | 25 (26.3%) |
| Oxygen | 10 (11.6%) | 12 (12.6%) |
| FVC% ≤60 | 26 (30.2%) | 34 (35.8%) |
*Median (IQR).
The number of patients undergoing the following measurements were: TLC: placebo 67, co-trimoxazole 74; Dlco: placebo 72, co-trimoxazole 77; 6MWT: placebo 43, co-trimoxazole 38; SGRQ: placebo 81, co-trimoxazole 87. Units are number of patients unless indicated.
Dlco, diffusing capacity of carbon monoxide; FVC, forced vital capacity; HRCT, high resolution CT; IPF, idiopathic pulmonary fibrosis; MRC, Medical Research Council; 6MWT, 6-minute walk test; NSIP, non-specific interstitial pneumonia; SGRQ, St George's Respiratory Questionnaire; TLC, total lung capacity; UIP, usual interstitial pneumonia.