Asbestos exposure, geometric mean (IQR); sex and smoking status, number (%) and x ray defined asbestosis, number (%) for 58 cases and 1930 controls from former workers and residents of Wittenoom
| Cases (n = 58) | Non-cases (n = 1930) | Total (n = 1988) | p value | |
|---|---|---|---|---|
| *Geometric mean. | ||||
| Mean (SD) | Mean (SD) | Mean (SD) | ||
| Age at start of study | 61 (8) | 52 (12) | 52 (12) | <0.001 |
| Time since first exposed (years) | 33 (6) | 31 (6) | 31 (6) | 0.0058 |
| Age at first exposure (years) | 27 (8) | 21 (11) | 21 (11) | <0.001 |
| Mean (IQR) | Mean (IQR) | Mean (IQR) | ||
| Duration of exposure (days)* | 330 (118–1048) | 285 (106–854) | 286 (106–868) | 0.4615 |
| Intensity of exposure (f/ml)* | 12 (6.2–40.3) | 6 (2.1–20.3) | 6 (2.1–20.3) | 0.0005 |
| Cumulative exposure (f/ml-year)* | 11 (2.6–46.5) | 5 (1.84–13.5) | 5 (1.87–14.0) | 0.0002 |
| n (%) | n (%) | n (%) | ||
| Sex | ||||
| Male | 52 (90) | 1400 (73) | 1452 (73) | 0.004 |
| Female | 6 (10) | 530 (27) | 536 (27) | |
| Smoking status | ||||
| Never | 1 (2) | 532 (28) | 533 (27) | <0.001 |
| Past | 33 (57) | 1010 (52) | 1043 (52) | |
| Current | 24 (41) | 388 (20) | 412 (21) | |
| Asbestosis | 21 (36%) | 220 (11%) | 241 (12%) | <0.001 |
| Distribution of asbestosis (ILO category) | ||||
| ⩽0/1 | 37 (64%) | 1710 (89%) | 1747 (88%) | <0.001 |
| 1/0, 1/1, 1/2 | 13 (22%) | 187 (10%) | 200 (10%) | |
| 2/1, 2/2, 2/3 | 7 (12%) | 27 (1%) | 34 (2%) | |
| 3/1, 3/2, 3/3 | 1 (2%) | 6 (0%) | 7 (0%) | |