[Neonatal morbidity of newborns less than 32 weeks of gestation who have a TSH rate higher than 10 mIU/L].

UNLABELLED

Thyroid hormones are involved in the development of human vital functions, especially in preterm infants. Hypothyroidism may have consequences in cardiac, respiratory, digestive, and neurological outcomes in this population. The main objective of this study was to evaluate neonatal morbidity in preterm newborns less than 32 weeks of gestation (WG), according to their thyroid stimulating hormone (TSH) rate. Secondly, we assessed the value of a treatment with synthesis thyroid hormones.

METHOD

In a retrospective study, two groups were compared as to whether they had a TSH rate higher or lower than 10 mIU/L. A second analysis was performed to evaluate the advantages of a treatment with L-thyroxine. Perinatal data and morbidity (hemodynamic support, respiratory failure, digestive and neurological functions) were evaluated.

RESULTS

From January 2006 to September 2011, 274 newborns under 32 WG were screened. Twenty-five newborns had a TSH rate greater than 10 mIU/L and were matched with 25 preterms having a TSH rate under 10 mIU/L. The incidence of patent ductus arteriosus was significantly higher in the group with TSH over 10 mIU/L (22 vs 6; P<0.001). In the group with TSH over 10 mIU/L, 13 newborns were treated. These were more oxygen-dependent at 28 days of life (7 vs 3; P=0.03) and were full fed later (14 days; 5.5 vs 12 days; 2; P=0.05).

CONCLUSION

A TSH rate higher than 10 mIU/L was associated with a higher incidence of patent ductus arteriosus in preterm newborns under 32 WG. Thyroid synthesis treatment does not improve respiratory or digestive short-term outcome.