Subject characteristics
| Parameter | Lost to follow up (n=132)‡ | Available for follow up (n=375)‡ | Actual follow up (n=319)† | |
|---|---|---|---|---|
| Working with animals >4 y (n=217)‡ | Working with animals <4 y (n=102)‡ | |||
| *p<0.05 for comparisons between subjects lost to follow up and subjects available for follow up or subjects in follow up population working with laboratory animals for >4 years and those working for <4 years, respectively. | ||||
| **p<0.01 for comparisons between subjects lost to follow up and subjects available for follow up or subjects in follow up population working with laboratory animals for >4 years and those working for <4 years, respectively. | ||||
| †Fifty six subjects who were available for follow up did not participate in lung function testing. | ||||
| ‡n (%)/mean (SD). | ||||
| §Percentage of predicted value (sex, age, and height corrected).27 | ||||
| Gender (female) | 51 (39%) | 143 (38%) | 60 (28%) | 56 (55%)** |
| Age (y) | 33.6 (9.0) | 35.4 (9.8) | 39.3 (8.7) | 28.6 (7.0)** |
| Standing height (cm) | 176.8 (8.7) | 175.9 (9.1) | 176.2 (8.8) | 175.9 (10.0) |
| Body weight (kg) | 73.9 (12.0) | 73.7 (11.9) | 74.6 (11.6) | 71.8 (12.0) |
| Current smoker | 44 (33%) | 86 (23%)* | 51 (24%) | 20 (20%) |
| Former smoker | 24 (18%) | 106 (28%)* | 78 (36%) | 15 (15%)** |
| Pack-years (y) | 4.1 (9.8) | 3.9 (7.7) | 5.1 (8.7) | 1.4 (4.0)** |
| Common atopy | 61 (46%) | 164 (44%) | 99 (46%) | 45 (44%) |
| Chronic respiratory symptoms | 48 (36%) | 97 (26%)* | 56 (26%) | 25 (25%) |
| Bronchitis symptoms | 19 (14%) | 26 (7%)** | 18 (8%) | 4 (4%) |
| Asthma symptoms | 36 (27%) | 84 (22%) | 47 (22%) | 23 (23%) |
| History of non-occupational allergy | 38 (29%) | 96 (26%) | 60 (28%) | 23 (23%) |
| Airway hyperreactivity | 22 (17%) | 54 (14%) | 28 (13%) | 17 (17%) |
| Years worked with laboratory animals (y) | 8.7 (7.9) | 10.8 (10.1)* | 15.9 (9.1) | 1.7 (1.1)** |
| Recently exposed to laboratory animals | 124 (94%) | 335 (89%) | 203 (94%) | 82 (80%)** |
| Sensitised to laboratory animals | 42 (32%) | 102 (27%) | 62 (29%) | 26 (25%) |
| Symptoms of respiratory allergy to laboratory animals | 37 (28%) | 56 (15%)** | 33 (15%) | 15 (15%) |
| FEV1 (%)§ | 106.9 (11.6) | 106.8 (13.4) | 108.0 (14.3) | 105.9 (11.6) |
| FVC (%)§ | 110.8 (11.8) | 111.0 (13.2) | 112.8 (14.1) | 109.3 (11.7)* |
| MMEF (%)§ | 92.8 (24.1) | 91.0 (25.0) | 90.2 (25.9) | 93.3 (23.6) |