Baseline background characteristics of participants in the West Sweden asthma study by age and sex
| WSAS I* | ||||||||||
| Frequency n=18 087 n (%) | ≤30 years n=3948 n (%) | 31–45 years n=4851 n (%) | 46–60 years n=4956 n (%) | 61–75 years n=4312 n (%) | ||||||
| Males n=8190 | Females n=9897 | Males n=1695 | Females n=2253 | Males n=2169 | Females n=2682 | Males n=2297 | Females n=2659 | Males n=2027 | Females n=2285 | |
| Education level | ||||||||||
| Less than high school High school Tertiary education Missing information | 1817 (22.2) 3385 (41.3) 2842 (34.7) 146 (1.8) | 2226 (22.5) 3427 (34.6) 4063 (41.1) 181 (1.8) | 179 (10.6) 904 (53.3) 568 (33.5) 44 (2.6) | 234 (10.4) 1068 (47.4) 922 (40.9) 29 (1.3) | 151 (7.0) 1030 (47.5) 960 (44.3) 28 (1.3) | 182 (6.8) 1019 (38.0) 1450 (54.1) 31 (1.2) | 542 (23.6) 937 (40.8) 783 (34.1) 35 (1.5) | 568 (21.4) 950 (35.7) 1107 (41.6) 34 (1.3) | 944 (46.6) 513 (25.3) 531 (26.2) 39 (1.9) | 1236 (54.1) 384 (16.8) 579 (25.3) 86 (3.8) |
| Smoking status | ||||||||||
| Non-smoker Ex-smoker Current smoker | 5202 (63.5) 1837 (22.4) 1151 (14.0) | 6227 (62.9) 2139 (21.6) 1531 (15.5) | 1369 (80.8) 97 (5.7) 229 (13.5) | 1650 (73.2) 203 (9.0) 400 (17.7) | 1552 (71.5) 330 (15.2) 287 (13.2) | 1801 (67.1) 497 (18.5) 384 (14.3) | 1259 (54.8) 669 (29.1) 369 (16.1) | 1426 (53.6) 778 (29.3) 455 (17.1) | 1021 (50.4) 741 (36.6) 265 (13.1) | 1343 (58.8) 655 (28.7) 287 (12.6) |
| Occupational exposure to gas, dust and fumes | ||||||||||
| No Yes | 5587 (68.2) 2603 (31.8) | 8551 (86.4) 1346 (13.6) | 1250 (73.7) 445 (26.2) | 1939 (86.1) 314 (13.9) | 1498 (69.1) 671 (30.9) | 2283 (85.1) 399 (14.9) | 1531 (66.6) 766 (33.3) | 2279 (85.7) 380 (14.3) | 1306 (64.4) 721 (35.6) | 2035 (89.1) 250 (10.9) |
| Raised on a farm | ||||||||||
| No Yes | 7004 (85.5) 1186 (14.5) | 8526 (86.2) 1371 (13.8) | 1544 (91.1) 151 (8.9) | 2091 (92.8) 162 (7.2) | 1964 (90.5) 205 (9.5) | 2443 (91.1) 239 (8.9) | 1926 (83.8) 371 (16.1) | 2223 (83.6) 436 (16.4) | 1568 (77.4) 459 (22.6) | 1757 (76.9) 528 (23.1) |
| Family history of allergy | ||||||||||
| No Yes | 5746 (70.2) 2444 (29.8) | 6010 (60.7) 3887 (39.3) | 952 (56.2) 743 (43.8) | 1054 (46.8) 1199 (53.2) | 1417 (65.3) 752 (34.7) | 1510 (56.3) 1172 (43.7) | 1705 (74.2) 592 (25.8) | 1731 (65.1) 928 (34.9) | 1670 (82.4) 357 (17.6) | 1704 (74.6) 581 (25.4) |
| WSAS II | ||||||||||
| Frequency n=24 534 n (%) | ≤30 years n=4209 n (%) | 31–45 years n=5502 n (%) | 46–60 years n=6957 n (%) | 61–75 years n=7866 n (%) | ||||||
| Males n=11 204 | Females n=13 330 | Males n=1787 | Females n=2422 | Males n=2456 | Females n=3046 | Males n=3135 | Females n=3822 | Males n=3826 | Females n=4040 | |
| Education level | ||||||||||
| Less than high school High school Tertiary education Missing information | 2096 (18.7) 4700 (41.9) 4294 (38.3) 114 (1.0) | 2152 (16.1) 4591 (34.4) 6415 (48.1) 172 (1.3) | 210 (11.7) 969 (54.2) 591 (33.1) 17 (1.0) | 220 (9.1) 1160 (47.9) 1020 (42.1) 22 (0.9) | 145 (5.9) 944 (38.4) 1343 (54.7) 24 (1.0) | 147 (4.8) 878 (28.8) 1995 (65.5) 26 (0.9) | 448 (14.3) 1467 (46.8) 1191 (38.0) 29 (0.9) | 352 (9.2) 1564 (40.9) 1865 (48.8) 41 (1.1) | 1293 (33.8) 1320 (34.5) 1169 (30.5) 44 (1.2) | 1433 (35.5) 989 (24.5) 1535 (38.0) 83 (2.0) |
| Smoking status | ||||||||||
| Non-smoker Ex-smoker Current smoker | 7167 (64.0) 2725 (24.3) 1312 (11.7) | 8585 (64.4) 3109 (23.3) 1636 (12.3) | 1406 (78.7) 134 (7.5) 247 (13.8) | 1865 (77.0) 201 (8.3) 356 (14.7) | 1804 (73.5) 376 (15.3) 276 (11.2) | 2226 (73.1) 537 (17.6) 283 (9.3) | 2095 (66.8) 664 (21.2) 376 (12.0) | 2336 (61.1) 974 (25.5) 512 (13.4) | 1862 (48.7) 1551 (40.5) 413 (10.8) | 2158 (53.4) 1397 (34.6) 485 (12.0) |
| Occupational exposure to gas, dust and fumes | ||||||||||
| No Yes | 8147 (72.7) 3057 (27.3) | 11 923 (89.4) 1407 (10.6) | 1385 (77.5) 402 (22.5) | 2161 (89.2) 261 (10.8) | 1865 (75.9) 591 (24.1) | 2732 (89.7) 314 (10.3) | 2258 (72.0) 877 (28.0) | 3425 (89.6) 397 (10.4) | 2639 (69.0) 1187 (31.0) | 3605 (89.2) 435 (10.8) |
| Raised on a farm | ||||||||||
| No Yes | 9892 (88.3) 1312 (11.7) | 11 814 (88.6) 1516 (11.4) | 1651 (92.4) 136 (7.6) | 2257 (93.2) 165 (6.8) | 2272 (92.5) 184 (7.5) | 2768 (90.9) 278 (9.1) | 2814 (89.8) 321 (10.2) | 3424 (89.6) 398 (10.4) | 3155 (82.5) 671 (17.5) | 3365 (83.3) 675 (16.7) |
| Family history of allergy | ||||||||||
| No Yes | 7711 (68.8) 3492 (31.2) | 8041 (60.3) 5289 (39.7) | 928 (51.9) 859 (48.1) | 1107 (45.7) 1315 (54.3) | 1514 (61.6) 942 (38.4) | 1624 (53.3) 1422 (46.7) | 2179 (69.5) 956 (30.5) | 2334 (61.1) 1488 (38.9) | 3090 (80.8) 736 (19.29 | 6066 (77.1) 1800 (22.9) |
* 20 participants had missing information for age and were therefore excluded from age-stratified analyses.
WSAS, West Sweden Asthma Study.