Effects of genetic and environmental factors on autoantibody outcomes (N = 47,729)
| Covariate | OR (95% CI) | P value |
|---|---|---|
| GADA as outcome | ||
| Age | 1.00 (0.995–1.005) | 0.9664 |
| Genetic factors (G) | 33.89 (11.54–99.48) | <0.0001 |
| Environmental factors (E) | 0.922 (0.614–1.385) | 0.697 |
| Sex (female) | 0.97 (0.89–1.05) | 0.453 |
| IA-2A as outcome | ||
| Age | 0.97 (0.96–0.98) | <0.0001 |
| Genetic factors (G) | 16.82 (4.10–69.72) | 0.0001 |
| Environmental factors (E) | 1.19 (0.71–2.00) | 0.521 |
| Sex (female) | 0.79 (0.70–0.89) | 0.0001 |
| IAA as outcome | ||
| Age | 0.95 (0.94–0.96) | <0.0001 |
| Genetic factors (G) | 15.28 (4.37–53.49) | <0.0001 |
| Environmental factors (E) | 1.48 (0.95–2.32) | 0.085 |
| Sex (female) | 0.75 (0.67–0.84) | <0.0001 |
| ≥1 positive autoantibody as outcome | ||
| Age | 1.00 (0.99–1.00) | 0.033 |
| Genetic factors (G) | 19.78 (7.64–51.21) | <0.0001 |
| Environmental factors (E) | 1.07 (0.77–1.51) | 0.681 |
| Sex (female) | 0.89 (0.83–0.96) | 0.002 |
| ≥2 positive autoantibodies as outcome | ||
| Age | 0.96 (0.95–0.97) | <0.0001 |
| Genetic factors (G) | 26.68 (7.43–95.84) | <0.0001 |
| Environmental factors (E) | 1.28 (0.80–2.07) | 0.307 |
| Sex (female) | 0.82 (0.73–0.92) | 0.0008 |
| Both IA-2A and IAA positive as outcome | ||
| Age | 0.92 (0.91–0.94) | <0.0001 |
| Genetic factors (G) | 19.61 (3.29–116.87) | 0.0011 |
| Environmental factors (E) | 1.67 (0.86–3.23) | 0.1286 |
| Sex (female) | 0.67 (0.57–0.83) | <0.0001 |
Logistic regression models testing the association of autoantibody outcomes, G (average fraction of genes shared identical by descent with affected proband), and E (environmental factors unique to twins [i.e., shared uterine environment]) adjusted for age and sex.