Table 1. Baseline Characteristics of Study Cohort.
| Characteristic | No. (%) | |
|---|---|---|
| Celiac disease (n = 49 829) |
Matched comparators (n = 246 426) |
|
| Female sex | 31 086 (62.4) | 154 056 (62.5) |
| Male sex | 18 743 (37.6) | 92 370 (37.5) |
| Age at diagnosis, y | ||
| Mean (SD) | 32.2 (25.2) | 31.9 (25.1) |
| Median (interquartile range) | 28.5 (8.4-53.5) | 28.0 (8.3-53.0) |
| Range | 0.0-95.4 | 0.0-95.8 |
| Age categories | ||
| <18 y | 19 632 (39.4) | 98 080 (39.8) |
| ≥18-<40 y | 10 913 (21.9) | 54 212 (22.0) |
| ≥40-<60 y | 9946 (20.0) | 49 268 (20.0) |
| ≥60 y | 9338 (18.7) | 44 866 (18.2) |
| Country of birth | ||
| No. of participants | 49 827 (100.0) | 246 414 (100.0) |
| Nordic country | 47 765 (95.9) | 226 192 (91.8) |
| Other country | 2062 (4.1) | 20 222 (8.2) |
| Level of education | ||
| No. of participants | 28 496 (57.2) | 139 930 (56.8) |
| ≤9 y | 8617 (30.2) | 44 048 (31.5) |
| 10-≤12 y | 11 856 (41.6) | 58 570 (41.9) |
| >12 y | 8023 (28.2) | 37 312 (26.7) |
| Parents’ highest level of education (used when patient’s level of education is missing | ||
| No. of applicable participants | 47 682 (95.7) | 235 572 (95.6) |
| ≤9 y | 9798 (20.5) | 50 987 (21.6) |
| 10-≤12 y | 20 090 (42.1) | 99 391 (42.2) |
| >12 y | 17 794 (37.3) | 85 194 (36.2) |
| Start year of follow-up | ||
| 1969-1989 | 4339 (8.7) | 21 604 (8.8) |
| 1990-1999 | 13 585 (27.3) | 67 331 (27.3) |
| 2000-2009 | 19 914 (40.0) | 98 232 (39.9) |
| 2010-2017 | 11 991 (24.1) | 59 259 (24.0) |
| Disease history before start of follow-up | ||
| Type 1 diabetes | 1565 (3.1) | 667 (0.3) |
| Inflammatory bowel disease | 1401 (2.8) | 365 (0.1) |
| Autoimmune thyroid disease | 1126 (2.3) | 1852 (0.8) |
| Rheumatoid arthritis | 423 (0.8) | 1096 (0.4) |
| Deaths | ||
| Days after index date | ||
| ≤30 | 114 (0.2) | 121 (<0.1) |
| ≤90 | 280 (0.6) | 401 (0.2) |
| ≤365 | 757 (1.5) | 1599 (0.6) |
| All follow-up time | 6596 (13.2) | 28 890 (11.7) |