The effect of the D1-C785T polymorphism in the type 1 iodothyronine deiodinase gene on the circulating thyroid hormone levels in Romanian women with preeclampsia. Association with the degree of severity and pregnancy outcome of preeclampsia.

AIM

To investigate the biochemical and genetic thyroid status in women with preeclampsia by the determination of serum FT3 and FT4 levels in association with D1-C785T genotypes.

METHODS

We genotyped using PCR-RFLP methods 50 women with preeclampsia and 50 normotensive pregnant women.

RESULTS

FT3 levels (pg/ml, 2.63 ± 0.56 vs. 2.91 ± 1.41) were low, and FT4 levels (ng/dl, 1.11 ± 0.3 vs. 0.88 ± 0.14) were high in women with preeclampsia compared to normal pregnant women. The association with severe preeclampsia was stronger for the homozygous T/T genotype (OR 6.57, p = 0.029). Women with preeclampsia with the D1-T785 mutated allele had lower FT3 levels (pg/ml, 2.31 ± 0.81 vs. 3.04 ± 0.39, p < 0.001), higher FT4 levels (ng/dl, 1.32 ± 0.87 vs. 0.84 ± 0.24, p = 0.009) than women with preeclampsia with the D1-C/C genotype. Significant decrease in serum FT3 levels in positive women with severe preeclampsia compared to women negative for this genetic variation (pg/ml, 1.59 ± 0.74 vs. 2.77 ± 0.23, p = 0.003) was observed. Women with severe preeclampsia, positive for the mutated T785 allele, delivered at a significantly lower gestational age (31.75 ± 3.69 vs. 38.66 ± 3.21 weeks, p = 0.035) neonates with a lower birth weight (1861.11 ± 869.9 vs. 3500 ± 424.26 g, p = 0.023) compared to women negative for the same allele.

CONCLUSIONS

Thyroid hormone levels and the D1-C785T polymorphism, alone or in combination, correlate with the severity of preeclampsia. The D1-C785T polymorphism influences the outcome of pregnancy in severe preeclampsia.