Table 1.
Description of Study Population
| No. /Total (%) of Participants | ||||
|---|---|---|---|---|
| All | Colorado | Finland | Germany | |
| Multiple islet autoantibody–positive | 585/13 377 (4.4) | 69/1962 (3.5) | 399/8597 (4.6) | 117/2818 (4.2) |
| Girls | 249/585 (42.6) | 34/69 (49.3) | 164/399 (41.1) | 51/117 (43.6) |
| Family history of type 1 diabetes | 201/585 (34.4) | 39/69 (56.5) | 45/399 (11.3) | 117/117 (100) |
| HLA DR3/DR4-DQ8 | 185/577 (32.1)a | 31/69 (44.9) | 119/399 (29.8) | 35/109 (32.1)a |
| Follow-up time, median (IQR), yb | 4.5 (2.3-7.2) | 5.6 (3.5-7.7) | 3.9 (2.2-6.9) | 5.3 (2.9-7.7) |
| Seroconversion age, median (IQR), y | 2.1 (1.3-4.1) | 3.1 (1.6-5.4) | 2.0 (1.3-4.0) | 2.1 (1.1-5.0) |
| Nonwhite race/ethnicity | 8/585 (1.4) | 6/69 (8.7) | 0/399 (0) | 2/117 (1.7) |
| Single islet autoantibody–positive | 474/13 377 (3.5) | 71/1962 (3.6) | 293/8597 (3.4) | 110/2818 (3.9) |
| Girls | 211/474 (44.5) | 34/71 (47.9) | 115/293 (39.2) | 62/110 (56.4) |
| Family history of type 1 diabetes | 161/474 (34.0) | 35/71 (49.3) | 17/293 (5.8) | 110/110 (100) |
| HLA DR3/DR4-DQ8 | 79/450 (17.5)a | 20/71 (28.2) | 51/276 (18.5)a | 8/103 (7.8)a |
| Follow-up time, median (IQR), yb | 5.5 (2.6-8.5) | 5.5 (2.9-7.8) | 5.5 (2.4-8.2) | 5.9 (2.8-10) |
| Seroconversion age, median (IQR), y | 4.8 (2.1-7.7) | 5.4 (2.6-9.2) | 3.9 (2.0-6.5) | 7.3 (3.3-9.8) |
| Nonwhite race/ethnicity | 9/474 (1.9) | 7/71 (9.9) | 0/293 (0) | 2/110 (1.8) |
| Autoantibody negative | 12 318/13 377 (92.1) | 1822/1962 (92.8) | 7905/8597 (91.9) | 2591/2818 (91.9) |
| Girls | 5807/12 318 (47.1) | 882/1822 (48.4) | 3662/7905 (46.3) | 1263/2591 (48.7) |
| Family history of type 1 diabetes | NA | 629/1822 (34.5) | NA | 2591/2591 (100) |
| HLA DR3/DR4-DQ8 | 1200/7298 (16.4)a | 404/1822 (22.2) | 613/4488 (13.7)a | 183/2188 (8.4)a |
| Follow-up time, median (IQR), yb | 8.9 (4.1-12.6) | 9.0 (3.3-14) | 8.9 (4.3-12.1) | 8.2 (4.8-13.5) |
| Nonwhite race/ethnicity | 204/13 377 (1.5) | 164/1822 (9.0) | 0/7905 (0) | 40/2591 (1.5) |
Abbreviations: HLA, human leukocyte antigen; IQR, interquartile range; NA, not available.
a
Full HLA DR-DQ genotype was unavailable in 8 children with multiple islet antibodies, 7 children with a single islet autoantibody, and 403 children with no islet autoantibodies from Germany; 17 children with a single islet autoantibody, and 3417 children with no islet autoantibodies from Finland.
b
Follow-up time from the age of seroconversion to the age at diabetes or last contact.