Psychomotor Development of Children with Congenital Hypothyroidism Diagnosed by Neonatal Screening

The psychomotor development in 68 children with congenital hypothyroidism diagnosed during the first two years of a nationwide neonatal screening programme in Sweden was assessed during their first three years of life. Replacement therapy with thyroxine was initiated at the age of 15 +/- 7 days (mean +/- SD). Griffiths tests were performed in 15 patients at the age of 18 months and in 51 patients at 30-47 months. Their developmental quotients did not differ from those of control children, indicating that the psychomotor development in the children with congenital hypothyroidism was normal. In earlier studies of Swedish children with congenital hypothyroidism, diagnosed clinically before the age of three and a half years, the psychomotor development was found to be impaired. In contrast, the patients diagnosed by neonatal screening and given early therapy displayed normal results in Griffiths tests. This indicates that the age at the start of treatment is an important determinant for the prognosis.