| Overall (n = 238) | Exposure | ||||||
---|---|---|---|---|---|---|---|---|
Reactive chemical (n = 26) | Inorganic dust (n = 74) | Organic dust (n = 63) | Contact with livestock (n = 15) | Close human contact (n = 31) | Admin work only (n = 42) | Active smoker (n = 43) | ||
Demographics | ||||||||
 Gender | ||||||||
  Women | 84 (35%) | 5 (19%)§ | 3 (4.1%)* | 22 (35%) | 6 (40%) | 25 (81%)* | 22 (52%)* | 9 (21%)* |
  Men | 154 (65%) | 21 (81%)§ | 71 (96%)* | 41 (65%) | 9 (60%) | 6 (19%)* | 20 (48%)* | 34 (79%)* |
 Age at diagnosis | 42 (35–50) | 37 (34–49) | 41 (35–48) | 39 (34–48)§ | 47 (38–52) | 44 (39–50) | 42 (36–46) | 38 (30–46)* |
Smoking | ||||||||
 Never smoker | 148 (62%) | 14 (54%) | 40 (54%)§ | 43 (68%) | 14 (93%)* | 21 (68%) | 30 (71%) | 0 (0%) |
 Past smoker | 47 (20%) | 6 (23%) | 17 (23%) | 13 (21%) | 1 (6.7%) | 5 (16%) | 6 (14%) | 0 (0%) |
 Active smoker | 43 (18%) | 6 (23%) | 17 (23%) | 7 (11%)§ | 0 (0%)§ | 5 (16%) | 6 (14%) | 43 (100%) |
 Packyears (for past or active smokers) | 10 (5–20) | 7.5 (5–20) | 10 (5–20) | 12 (5–20) | 45 | 5 (5–14) | 10 (9–15) | 10 (6–20) |
Chest CT at diagnosis | ||||||||
 Enlarged hilar/mediastinal lymph nodes | 235 (99%) | 25 (96%) | 73 (99%) | 63 (100%) | 15 (100%) | 31 (100%) | 40 (95%)§ | 43 (100%) |
 (Micro)nodules | 183 (77%) | 21 (81%) | 55 (74%) | 51 (81%) | 10 (67%) | 22 (71%) | 35 (83%) | 36 (84%) |
 Fibrotic changes | 13 (5.5%) | 2 (7.7%) | 4 (5.4%) | 2 (3.2%) | 0 (0%) | 2 (6.5%) | 5 (12%)§ | 4 (9.3%) |
 Airway abnormalities | 44 (18%) | 7 (27%) | 20 (27%)* | 9 (14%) | 1 (6.7%) | 3 (9.7%) | 8 (19%) | 10 (23%) |
Lung function at diagnosis | ||||||||
 FVC %pred | 94 (85–105) | 91 (77–102) | 94 (81–103) | 90 (78–98)* | 94 (91–103) | 99 (86–108) | 94 (90–108)§ | 94 (81–106) |
 FEV1%pred | 89 (76–102) | 84 (70–98) | 89 (75–104) | 82 (71–92)* | 92 (87–98) | 90 (77–102) | 94 (80–106) | 81 (70–99)§ |
 FEV1/FVC% | 78 (73–83) | 76 (62–82)§ | 77 (74–82) | 76 (70–80)* | 80 (77–82) | 81 (71–85) | 80 (76–83)§ | 78 (67–83) |
 TLC %pred | 92 (83–100) | 88 (80–99) | 89 (80–98)§ | 86 (80–98)§ | 91 (86–97) | 94 (89–102) | 96 (88–100)§ | 86 (80–101) |
 TLCO %pred | 80 (68–92) | 74 (64–93) | 81 (67–95) | 80 (68–88) | 84 (74–96) | 81 (68–87) | 79 (69–90) | 73 (62–89)* |
Broncho-alveolar lavage | ||||||||
 % Lymphocytes | 17 (10–25) | 19 (14–25) | 15 (10–21) | 15 (10–23) | 13 (7–33) | 18 (11–32) | 15 (7–25) | 14 (7–21) |
  Not available | 125 (53%) | 13 (50%) | 34 (46%) | 27 (43%) | 9 (60%) | 20 (65%) | 24 (57%) | 21 (49%) |
Treatment | ||||||||
 Treated within first year after diagnosis | 118 (50%) | 10 (38%) | 41 (55%) | 33 (52%) | 5 (33%) | 16 (52%) | 21 (50%) | 26 (60%) |
  Oral corticosteroids | 116 (49%) | 10 (38%) | 41 (55%) | 33 (52%) | 5 (33%) | 16 (52%) | 19 (45%) | 26 (60%)§ |
  Methotrexate | 46 (19%) | 5 (19%) | 17 (23%) | 14 (22%) | 0 (0%)§ | 5 (16%) | 7 (17%) | 16 (37%)* |
  Azathioprine | 47 (20%) | 6 (23%) | 17 (23%) | 15 (24%) | 1 (6.7%) | 5 (16%) | 10 (24%) | 14 (33%)* |
  Chloroquine | 27 (11%) | 4 (15%) | 12 (16%) | 8 (13%) | 0 (0%) | 3 (9.7%) | 4 (9.5%) | 10 (23%)* |