TABLE 2

Type 1 diabetes risk in relation to islet autoantibody titer, IgG subclass, and epitope reactivity in autoantibody-positive relatives: univariate analysis

VariablenType 1 diabetes (n)10-year diabetes risk (% ± SE)HR (95% CI)P
Autoantibody titer
 GADA0.19
  First quartile371135 ± 91*
  Second quartile37822 ± 90.8 (0.3–1.9)0.55
  Third quartile371752 ± 91.7 (0.8–3.6)0.18
  Fourth quartile381343 ± 101.6 (0.7–3.6)0.26
 IAA0.01
  First quartile18645 ± 161*
  Second quartile18430 ± 130.7 (0.2–2.4)0.55
  Third quartile18438 ± 170.8 (0.2–2.7)0.68
  Fourth quartile181277 ± 123.0 (1.1–8.1)0.03
 IA-2A0.04
  First quartile15320 ± 141*
  Second quartile15974 ± 156.0 (1.6–22.4)0.008
  Third quartile161284 ± 105.9 (1.7–21.1)0.006
  Fourth quartile16971 ± 154.8 (1.3–17.9)0.02
Autoantibody IgG subclass
 GADA0.36
  IgG2, 3, and 4 negative832435 ± 71*
  IgG2, 3 or 4 positive662543 ± 71.3 (0.7–2.3)
 IAA0.009
  IgG2, 3, and 4 negative33728 ± 91*
  IgG2, 3, or 4 positive391968 ± 103.2 (1.2–7.6)
 IA-2A0.0001
  IgG2, 3, and 4 negative331137 ± 101*
  IgG2, 3, or 4 positive29221004.9 (2.2–10.6)
Autoantibody epitopes
 GADA0.18
  Single34932 ± 91*
  Multiple1154041 ± 61.6 (0.8–3.4)
 IA-2A0.048
  Single281150 ± 121*
  Multiple342275 ± 92.1 (1.0–4.3)
 IA-2A0.005
  IA-2β negative321138 ± 101*
  IA-2β positive302286 ± 82.9 (1.4–6.0)
  • *

    * Reference cell used in Cox’s proportional hazard model.