TABLE 1.
Characteristics of the cohort and results of Cox regression survival analysis of progression from islet autoimmunity to type 1 diabetes
| Progressed to type 1 diabetes (n = 50) | No type 1 diabetes (n = 90) | Unadjusted HR (95% CI) | Adjusted HR (95% CI)† | |
|---|---|---|---|---|
| Age (years) at diagnosis of type 1 diabetes | 8.7 (1.9–15) | |||
| Follow-up (years) from onset of islet autoimmunity | 4.1 (0.2–11) | 4.6 (1.6–14) | ||
| Positive for >2 islet autoantibodies at the first and/or second positive visit | 36 (72%) | 21 (23.3%) | 4.57 (2.46–8.51) | 4.24 (2.26–7.95) |
| Female sex | 26 (52%) | 48 (53.3%) | 1.18 (0.67–2.06) | 1.41 (0.79–2.50) |
| First-degree relative with type 1 diabetes‡ | 35 (70%) | 53 (58.9%) | 1.23 (0.67–2.26) | 1.13 (0.61–2.10) |
| HLA DRB1*04-DQB1*0302/DRB1*03-DQB1*0201 | 26 (52.0%) | 27 (30.0%) | 1.84 (1.06–3.21) | 1.51 (0.86–2.67) |
| Non–Hispanic white ethnicity§ | 46 (92.0%) | 72 (80.0%) | 1.94 (0.70–5.39) | 1.45 (0.51–4.13) |
| Age (years) when first islet autoantibody positive¶ | 3.1 (0.7–12) | 5.2 (0.7–13) | 0.93 (0.85–1.02) | 1.01 (0.091–1.11) |
Data are median (range) or n (%) unless otherwise indicated.
†Estimates from Cox regression model simultaneously adjusting for multiple autoantibodies in first two visits, HLA high risk genotype, presence of first-degree relative with type 1 diabetes, and age when first positive for islet autoantibodies.
‡Of these, 35 had an affected father only, 16 had an affected mother only, 34 had an affected sibling, and 3 had a sibling and a parent with type 1 diabetes.
§Ethnic group was self-reported. There were 118 non–Hispanic whites, 19 Hispanics, one African American, and two children of mixed ethnicity in the cohort.
¶HRs per year increase in age when first positive for islet autoantibodies.