Table 5.

Odds ratios (OR) for coeliac disease concordance among non-index twins, estimated by logistic regression

Characteristic	Concordant pairs for CD	Adjusted OR (95% CI)
Zygosity and No of shared haplotypes
DZ sharing 0 or 1 haplotype	2/21 (10%)	1.0
DZ sharing 2 haplotypes	1/6 (17%)	1.4 (0.0–27.4)
MZ	15/20 (75%)	17.0 (2.1–134.0)
DQ genotype
Not DQ2 or DQ8	2/12 (17%)	1.0
DQ2	15/29 (52%)	3.3 (0.4–30.0)
DQ8	1/6 (17%)	1.4 (0.0–41.0)
Sex of the non-index twin
Male	6/22 (27%)	1.0
Female	12/25 (48%)	1.3 (0.2–8.5)
Age at enrolment (y)
≤10	5/17 (29%)	1.0
11–30	9/22 (41%)	1.6 (0.2–11.0)
>30	4/8 (50%)	2.2 (0.2–27.7)

MZ, monozygotic, DZ, dizygotic.

95% CI, 95% confidence interval.