Neurodevelopmental outcomes in children with congenital hypothyroidism

Abstract

Although prognosis of Congenital Hypothyroidism (CH) has been greatly modified since the introduction of newborn screening programs, persistent cognitive deficits are still reported. The aim of this study was to evaluate neurodevelopmental outcomes of children with CH and to determine whether severity of CH, age of start of L-thyroxine supplementation and control of CH play an important role. We analyzed a sample of children with CH (N=44) using neurodevelopmental assessment tests according to child’s age and level of functioning: Griffiths Scale of Mental Development (GSMD), Portuguese version of Wechsler Intelligence Scale for Children – Third Edition (WISC-III), and Vineland Adaptive Behaviour Scale (VABS) and early developmental milestones. We further compared this data with screening TSH values and follow-up mean values of TSH, fT4 and L-thyroxine dosage. Communication Disorders and Attention-Deficit/Hyperactivity Disorder were the most common diagnosis, 25% and 15.9% respectively, found among children with neurodevelopmental problems (59.1%). Average scores in Practical Reasoning Quotient in the Griffiths subscale and Adaptive Behaviour Composite, Daily Living Skills and Socialization (VABS domains) in children with CH were significantly lower than in normal population. A correlation was found between mean L-thyroxine dosage and Full Scale Intelligence Quotient (WISC-III). No correlation was found between screening level of TSH, age of treatment initiation, follow-up mean TSH, mean fT4 values and results in the three global scales of neurodevelopmental tests. Even though prognosis of CH has been greatly modified since early detection through screening programs, careful monitoring of these children is crucial to guarantee an early intervention and to assure optimal neuro- and sociodevelopmental outcomes.