Table 1.
Characteristics of subjects in the TEDDY nested case-control study
| Matching variable | Case subjects, n (%) | Plasma 25(OH)D concentration (nmol/L) |
|||
|---|---|---|---|---|---|
| Childhood* |
Early infancy† |
||||
| Case subjects | Control subjects | Case subjects | Control subjects | ||
| Clinical center |
|||||
| Colorado |
55 (14.6) |
50.6 ± 17.8 |
56.1 ± 15.4 |
42.6 ± 25.7 |
44.8 ± 22.6 |
| Georgia |
23 (6.1) |
58.3 ± 20.0 |
59.3 ± 17.0 |
51.2 ± 21.8 |
53.7 ± 21.1 |
| Washington |
35 (9.3) |
51.3 ± 14.6 |
56.1 ± 17.1 |
44.2 ± 18.7 |
46.7 ± 24.9 |
| Finland |
112 (29.8) |
43.1 ± 13.0 |
44.9 ± 13.7 |
41.1 ± 15.0 |
43.0 ± 15.8 |
| Germany |
29 (7.7) |
57.3 ± 23.1 |
65.0 ± 19.8 |
56.1 ± 29.9 |
64.1 ± 22.3 |
| Sweden |
122 (32.5) |
56.5 ± 14.6 |
59.5 ± 14.8 |
53.9 ± 20.3 |
60.4 ± 20.8 |
| Sex |
|||||
| Female |
167 (44.4) |
51.7 ± 17.0 |
54.2 ± 17.2 |
47.5 ± 21.5 |
49.8 ± 22.0 |
| Male |
209 (55.6) |
51.0 ± 16.7 |
55.0 ± 16.4 |
47.3 ± 21.4 |
52.2 ± 21.6 |
| FDR/GP status |
|||||
| FDR |
91 (24.2) |
47.4 ± 17.2 |
56.8 ± 17.3 |
42.5 ± 20.8 |
54.4 ± 23.3 |
| GP | 285 (75.8) | 52.6 ± 16.5 | 53.9 ± 16.5 | 48.9 ± 21.4 | 50.1 ± 21.2 |
Data are mean ± SD, unless otherwise stated. FDR, first-degree relative of an individual with type 1 diabetes;
GP, from the general population (no first-degree relative with type 1 diabetes).
*Average of measures from all visits prior to and including the seroconversion visit, which is the first of two consecutive visits at which the child tested positive for an autoantibody.
†Defined by the first 25(OH)D measure occurring before 12 months of age in 360 case subjects and their 981 control subjects.