Effect of age at thyroid stimulating hormone normalization on postural control in children with congenital hypothyroidism

Neonatal screening programmes allow early treatment to limit the consequences of congenital hypothyroidism on maturation of the central nervous system, and on psychomotor and educational outcome. Consequences of age at thyroid stimulating hormone (TSH) normalization on postural control were evaluated in 17 children with congenital hypothyroidism (14 females, three males; median age 12 years 1 month, range 7 to 14 years) and in 11 control individuals (eight females, three males: median age 10 years 6 months, range 8 to 14 years). Children with congenital hypothyroidism were split into two groups according to time of TSH normalization: before (group 1) or after (group 2) 3 months of age. Posturography (static and dynamic tests), educational (school performance), and psychomotor (WISC and revised Bruininks Oseretsky tests) evaluations were carried out. Group 2 results showed significant abnormalities in postural, educational, and psychomotor aptitudes in comparison with group 1 and control children (stability, Bruininks-Oseretsky, school performance: pless than or equal to0.05 or pless than or equal to0.01). Early TSH normalization is necessary to allow for normal development of the neurosensorial afferent pathways (vestibular, proprioceptive) and of central integration (cerebellum, vestibular nuclei).