Distribution of characteristics for PiMM and PiMZ carriers
| SERPINA 1 genotype | PiMM | PiMZ |
|---|---|---|
| Number of participants | n=3642 | n=97 |
| Lung function at baseline | ||
| FEV1, L, mean (SD) | 3.64 (0.81) | 3.70 (0.79) |
| FVC, L, mean (SD) | 4.61 (1.02) | 4.60 (0.97) |
| FEV1/FVC, %, mean (SD) | 79.2 (7.5) | 81.0 (8.0) |
| FEF25–75, L/s, mean (SD) | 3.49 (1.21) | 3.81 (1.31) |
| Annual change in lung function from baseline to follow-up | ||
| ▵FEV1, mL, mean (SD) | −35 (31) | −37 (26) |
| ▵FVC, mL, mean (SD) | −24 (41) | −23 (42) |
| ▵FEV1/FVC, %, mean (SD) | −0.4 (0.5) | −0.5 (0.5) |
| ▵FEF25–75, mL/s, mean (SD) | −71 (65) | −88 (75) |
| Covariates of interest at baseline | ||
| Age, years, mean (SD) | 40.4 (11.2) | 39.5 (10.9) |
| BMI, kg/m2, mean (SD) | 23.7 (3.6) | 23.5 (3.4) |
| Height, cm, mean (SD) | 169.9 (8.8) | 169.6 (9.5) |
| Male, n (%) | 1845 (50.6) | 47 (48.5) |
| Early respiratory infection, n (%) | 321 (8.1) | 6 (6.2) |
| Parental history of asthma, n (%) | 381 (10.5) | 13 (13.4) |
| Education level, n (%) | ||
| High | 650 (17.9) | 25 (25.8) |
| Medium | 2585 (71.0) | 67 (69.1) |
| Low | 407 (11.2) | 5 (5.2) |
| ETS and smoking status at follow-up | ||
| Daily ETS exposure in past 12 months prior to follow-up, n (%) | ||
| ≥3 h/day | 355 (9.8) | 4 (4.1) |
| <3 h/day | 560 (15.4) | 15 (15.5) |
| Unexposed | 2727 (74.9) | 78 (80.4) |
| Smoking status through follow-up, n (%) | ||
| Persistent smokers | 877 (24.1) | 20 (20.6) |
| Former smokers | 1178 (32.3) | 28 (28.9) |
| Never smokers | 1587 (43.6) | 49 (50.5) |
| Cumulative pack-years through follow-up, mean (SD) | 10.7 (18.3) | 9.7 (15.6) |
| Occupational VGDF exposure | ||
| VGDF level in current occupation at baseline survey, n (%) | ||
| High | 479 (13.2) | 7 (7.2) |
| Low | 1190 (32.7) | 29 (29.9) |
| Unexposed | 1973 (54.2) | 61 (62.9) |
| Cumulative VGDF exposure at baseline survey among exposed, years, mean (SD) | 13.3 (28.0) | 10.5 (25.3) |
| Highest VGDF level in all occupations during follow-up, n (%) | ||
| High | 490 (13.5) | 9 (9.3) |
| Low | 1178 (32.3) | 34 (35.1) |
| Unexposed | 1974 (54.2) | 54 (55.7) |
| Cumulative VGDF exposure during follow-up among exposed, years, mean (SD) | 7.2 (12.4) | 5.4 (9.6) |
| Outdoor PM10 exposure | ||
| 1-year average PM10 prior to baseline survey, μg/m3, mean (SD) | 27.0 (9.8) | 27.0 (10.1) |
| Change in PM10 between follow-up and baseline surveys, μg/m3, mean (SD) | −6.2 (4.2) | −6.5 (5.0) |
ETS, environmental tobacco smoke; FVC, forced vital capacity; FEF, forced expiratory flow; FEV, forced expiratory volume; VGDF, vapours, dusts, gases and fumes.