Neurodevelopmental Impact of Treatment in Hypothyroxinaemia of Prematurity. (NEO-TYR)

Civil Hospices of Lyon

Status: Completed

Conditions: Transient Hypothyroxinemia of Prematurity

Treatments: Drug: L-thyroxine at a dose of 7.5 µg/kg/d for THOP; Other: THOP without treatment; Other: NoTHOP

Study type: Observational

Funder types: Other

Identifiers

NCT06346236

69HCL21_0843

401

Details and patient eligibility

About

Nowadays, taking care of preterm birth is associated with an important increase in survival. This increased survival comes with impairment in neurodevelopmental outcomes in long term evaluation. Thyroid hormones are essentials for brain development, especially for neuronal differentiation. Transient hypothyroxinaemia of prematurity (THOP) is a frequent condition defined by decreased thyroid hormones without the expected rise in thyroid stimulating hormone. Various studies have showed various results regarding the consequences of THOP on neurodevelopment in premature neonates. However, the biggest and most powerful studies agree to say that THOP impair neurodevelopment. On the other hand, only a few studies evaluated the impact of treatment of THOP, and only two focused on treating exclusively the neonates with a biological diagnosis of THOP (Suzumura and co. in 2010 and Nomura and co. in 2014) and their results are inconsistent.

In this study, we aim to show that a treatment with L-thyroxine at a dose of 7.5 µg/kg/j for neonates diagnosed with THOP (defined as a level of l-T4 < 12 pmol/L and a level of TSH < 15 mUI/L before 15 days of life or < 85 mUI/L after 15 days of birth) is associated with an increased neurodevelopmental prognosis.

Enrollment: 373 patients

Sex: All

Ages: Under 2 weeks old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Premature infants born before or at 3032 weeks of gestation
• For whom blood sample for thyroid examination has been performed for routine care during his stay in neonatology unit.

Exclusion criteria

• Other type of thyroid dysfunction (including, but not exclusively: mother with Basedow disease, congenital hypothyroidism, hyperthyroidism)
• Associated polymalformative sindrome

Trial design

373 participants in 3 patient groups

THOP treated

Description:

Level of circulating T4 \< 12 pmol/L at any time of life associated, on the same date, with a level of circulatingon thyro-stimulating hormone \< 15 mUI/L if the sample was realiszed before or on the fifteenth day of life OR \< 58 mUI/L if the sample was realiszed after the fifteenth day of life, and L-thyroxine treatment is recorded in the medical record (at any dose and with any duration)

Treatment:

Drug: L-thyroxine at a dose of 7.5 µg/kg/d for THOP

THOP un-treated

Description:

Level of circulating T4 \< 12 pmol/L at any time of life associated, on the same date, with a level of circulation thyro-stimulating hormone \< 15 mUI/L if sample was realiszed before or on the fifteenth day of life OR \< 5 mUI/L if sample was realiszed after the fifteenth day of life, and no L-thyroxine treatment recorded in the medical record.

Treatment:

Other: THOP without treatment

No-THOP

Description:

all level of circulating T4 \> 12 pmol/L at any time in life

Treatment:

Other: NoTHOP