Cerebral Cortical Thickness Morphometry and Neurocognitive Correlations in Adolescents With Congenital Hypothyroidism.

CONTEXT: Subtle cognitive impairments have been described in children with congenital hypothyroidism (CH) detected by neonatal screening (NS), even with early and adequate treatment. Patients with CH may present with brain cortical thickness (CT) abnormalities, which may be associated with neurocognitive impairments. OBJECTIVE: This work aimed to evaluate the CT in adolescents with CH detected by the NS Program (Paraná, Brazil), and to correlate possible abnormalities with cognitive level and variables of neurocognitive prognosis. METHODS: A review was conducted of medical records followed by psychometric evaluation of adolescents with CH. Brain magnetic resonance imaging with analysis of 33 brain areas of each hemisphere was performed in 41 patients (29 girls) and in a control group of 20 healthy adolescents. CT values were correlated with Full-scale Intelligence Quotient (FSIQ) scores, age at start of treatment, pretreatment thyroxine levels, and maternal schooling. RESULTS: No significant difference in CT between patients and controls were found. However, there was a trend toward thinning in the right lateral orbitofrontal cortex among patients and in the right postcentral gyrus cortex among controls. CT correlated significantly with FSIQ scores and with age at start of treatment in 1 area, and with hypothyroidism severity in 5 brain areas. Maternal schooling level did not correlate with CT but was significantly correlated with FSIQ. Cognitive level was within average in 44.7% of patients (13.2% had intellectual deficiency). CONCLUSION: There was a trend toward morphometric alterations in the cerebral cortex of adolescents with CH compared with healthy controls. The correlations between CT and variables of neurocognitive prognosis emphasize the influence of hypothyroidism on cortical development. Socioeconomic status exerts a limiting factor on cognitive outcome.

Cognitive outcome of 458 children over 25 years of neonatal screening for congenital hypothyroidism.

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.

Cognitive outcome of 458 children over 25 years of neonatal screening for congenital hypothyroidism

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.