Table 2.
Covariate summary statistics for patients with complete data on all analysis variables and belonging to valid matched sets.* Values are mean (percentage) unless stated otherwise
| Characteristic | Without atopic eczema (n=1 528 477) (79.8%)) | With atopic eczema (n=387 439 (20.2%)) | Total (n=1 915 916) |
|---|---|---|---|
| Follow-up (years) | |||
| Median (interquartile range) | 4.9 (2.0-9.6) | 5.7 (2.4-10.3) | 5.1 (2.0-9.8) |
| At entry to cohort | |||
| Sex: | |||
| Male | 511 676 (33.5) | 139 908 (36.1) | 651 584 (34.0) |
| Female | 1 016 801 (66.5) | 247 531 (63.9) | 1 264 332 (66.0) |
| Age (years): | |||
| 18-19 | 87 600 (5.7) | 36 392 (9.4) | 123 992 (6.5) |
| 20-29 | 275 632 (18.0) | 66 156 (17.1) | 341 788 (17.8) |
| 30-39 | 315 206 (20.6) | 70 222 (18.1) | 385 428 (20.1) |
| 40-49 | 272 436 (17.8) | 61 898 (16.0) | 334 334 (17.5) |
| 50-59 | 243 469 (15.9) | 55 294 (14.3) | 298 763 (15.6) |
| 60-69 | 195 936 (12.8) | 49 420 (12.8) | 245 356 (12.8) |
| 70-79 | 104 132 (6.8) | 33 837 (8.7) | 137 969 (7.2) |
| ≥80 | 34 066 (2.2) | 14 220 (3.7) | 48 286 (2.5) |
| Index of multiple deprivation: | |||
| 1 (least deprived) | 370 953 (24.3) | 94 223 (24.3) | 465 176 (24.3) |
| 2 | 332 853 (21.8) | 84 297 (21.8) | 417 150 (21.8) |
| 3 | 312 836 (20.5) | 78 603 (20.3) | 391 439 (20.4) |
| 4 | 273 332 (17.9) | 69 223 (17.9) | 342 555 (17.9) |
| 5 (most deprived) | 238 503 (15.6) | 61 093 (15.8) | 299 596 (15.6) |
| Body mass index: | |||
| Underweight | 45 488 (3.0) | 11 590 (3.0) | 57 078 (3.0) |
| Normal weight | 709 903 (46.4) | 174 234 (45.0) | 884 137 (46.1) |
| Overweight | 484 434 (31.7) | 123 352 (31.8) | 607 786 (31.7) |
| Obese | 288 652 (18.9) | 78 263 (20.2) | 366 915 (19.2) |
| Smoking status: | |||
| Non | 699 570 (45.8) | 168 221 (43.4) | 867 791 (45.3) |
| Current | 480 780 (31.5) | 116 551 (30.1) | 597 331 (31.2) |
| Former | 348 127 (22.8) | 102 667 (26.5) | 450 794 (23.5) |
| Diabetes | 51 213 (3.4) | 15 777 (4.1) | 66 990 (3.5) |
| Hypertension | 190 217 (12.4) | 58 001 (15.0) | 248 218 (13.0) |
| Hyperlipidaemia | 59 376 (3.9) | 19 342 (5.0) | 78 718 (4.1) |
| Depression | 300 699 (19.7) | 95 131 (24.6) | 395 830 (20.7) |
| Anxiety | 194 289 (12.7) | 65 248 (16.8) | 259 537 (13.5) |
| Asthma | 190 728 (12.5) | 91 955 (23.7) | 282 683 (14.8) |
| Severe alcohol use | 28 803 (1.9) | 8730 (2.3) | 37 533 (2.0) |
*
Matched sets including one exposed patient and at least one unexposed patient.