Abstract Objectives: To describe the neurocognitive profile of 458 children with congenital hypothyroidism detected by neonatal screening, followed under the same treatment protocol over 25 years. To correlate estimated full-scale IQ (FSIQ) scores with age at the start of treatment, disease severity, and maternal education. Methods: Observational, analytical, retrospective, and longitudinal cohort study, that evaluated children detected between 1991 and 2014, who underwent at least one psychometric assessment (WPPSI- R and/or WISC-III). Estimated FSIQ scores are described and correlated with prognosis determinants. Results: Median T4 at diagnosis was 2.8 µg/dL (0.0-16.5), the median age at the start of treatment was 18.5 days (3-309). Maternal education (n = 445): 2.7% of illiteracy, 59.8% with basic education. Estimated FSIQ scores were 88.0 (±11.8) in WPPSI-R (age 5.6 ± 0.5 years) and 84.1 (±13.0) in WISC-III (age 9.1 ± 1.4 years). The intellectual deficit was identified in 11.6%. Correlation between age at the start of treatment and estimated FSIQ was found only in the WPPSI-R test (p = 0.02). Initial T4 and maternal education significantly correlated with estimated FSIQ scores in both tests, with the latter being the most important determining factor. Conclusions: In this large cohort of mainly low socioeconomic status children, most children achieved normal cognitive levels; however, a significant percentage presented with below-average estimated FSIQ scores and intellectual deficits. Maternal education was the main determining factor in cognitive level followed by hypothyroidism severity.

Crianças nascidas prematuras podem passar por um período de restrição do crescimento logo após o nascimento. A normalização do crescimento tem início nos primeiros meses de vida, podendo ocorrer de forma lenta e progressiva. Muitas vezes essas crianças mantêm-se mais baixas e com menor peso durante toda a infância quando comparadas àquelas nascidas a termo. Em alguns casos, a recuperação completa só ocorre na adolescência. Entretanto, algumas crianças não conseguem recuperar totalmente o ganho de peso e altura, e adultos nascidos prematuros apresentam maior risco de baixa estatura. O comprometimento do crescimento é mais significativo naquelas nascidas prematuras e pequenas para a idade gestacional. Fatores como estatura-alvo, peso ao nascimento, idade gestacional, intercorrências neonatais e escolaridade materna interferem no potencial de crescimento. Especial atenção deve ser dada aos nascidos prematuros durante todo o período de crescimento.

Children born prematurely might experience a period of growth restriction just after birth. Catch-up growth begins during the first months of life and can be slow and progressive. These children may remain shorter and thinner throughout infancy and childhood compared to children born at term. In some cases, complete catch-up growth occurs only during adolescence. However, some children do not completely recover growth, and adults born prematurely are at increased risk of short stature. Impaired growth is more frequent in those born preterm and small for gestational age. Factors such as target height, birth weight, gestational age, neonatal morbidities and maternal education interfere in growth potential. Special attention should be given to children born preterm during the whole growth period.