Table 2 Characteristics of the study population
| Â | Tsukuba GWAS cohort | Tsukuba replication cohort | Hokkaido replication cohort | |||
|---|---|---|---|---|---|---|
Nonasthmatic individuals | Asthmatic patients | Nonasthmatic individuals | Asthmatic patients | Nonasthmatic individuals | Asthmatic patients | |
Number of participants | 734 | 237 | 375 | 381 | 554 | 428 |
Sex (female, %) | 499 (68.0) | 142 (59.9) | 251 (66.9) | 276 (72.4) | 314 (56.7) | 295 (68.9) |
Age, y (range) | 49.3 (27–74) | 51.4 (20–75) | 49.5 (22–78) | 59.0 (19–100) | 43.5 (18–84) | 49.5 (16–83) |
Age of asthma onset (range) | 37.9 (0–70) |  | 41.4 (1–88) |  | 34.0 (0–80) | |
Smoking (%) | ||||||
 Pack-year 0 | 607 (82.7) | 196 (82.7) | 311 (82.9) | 313 (82.2) | 492 (88.8) | 331 (77.3) |
 0–10 | 127 (17.3) | 41 (17.3) | 64 (17.1) | 68 (17.8) | 62 (11.2) | 97 (22.7) |
 Atopy (%) | 412 (56.1) | 151 (63.7) | 257 (68.5) | 175 (72.6) | 304 (55.1) | 300 (70.8) |
 FEV1% pred. (%, SD) | 94.6 (12.3) | 89.9 (20.1) | 89.3 (14.1) | 84.4 (23.2) | 106.7 (14.5) | 85.2 (23.8) |
 Serum IgE (log, SD) | 1.68 (0.55) | 2.22 (0.61) | 1.90 (0.64) | 2.18 (0.66) | 1.80 (0.63) | 2.27 (0.67) |