|Title / Titel||Congenital Hypothyroidism: Long-term Intellectual and Outcome after Early High-Dose Treatment|
|Abstract (PDF, 14 KB)|
|Summary / Zusammenfassung||Objective: To determine the long-term intellectual and motor outcome of children with early high-dose treated congenital hypothyroidism (CH) and to examine whether etiology, endocrinological parameters at diagnosis, socioeconomic status (SES) and treatment course were related to outcome.
Patients and Methods: The sample consisted of 63 prospectively followed children with CH. Intellectual performance was assessed at age 14 years with the Wechsler Intelligence Scale for Children-Revised (WISC-R) and compared to 175 controls.
Results:Median age at onset of treatment was 9 days (range 5-18 days) and median starting dose of levothyroxine (L-T4) was 14.7 µg/kg/day (range 9.9-23.6 µg/kg/day). Full-scale IQ of CH children was within normal limits, but significantly lower than in controls (101.7, versus 111.4; adjusted average difference 9.7 IQ scores, p<0.0001). Twenty-one percent had IQ scores more than 2 SD below the mean of the controls compared to 4 percent in the control group (p=0.0007). Children with an athyreosis had a lower performance IQ than those with a dysgenesis (adjusted average difference 7.6 IQ scores, p<0.05). Lower thyroxine (T4) levels at birth correlated with poorer IQ scores (r=0.27, p=0.04). Pre-treatment thyroid-stimulating hormone (TSH) levels, age at onset of treatment and starting dose of L-T4 were not related to outcome. There was a significant interaction (p=0.03) in the performance IQ for SES and group (CH versus control): differences in IQ scores between CH and controls increased with decreasing SES. Median L-T4, T4 and TSH levels and levels outside reference ranges throughout childhood were not related to intellectual outcome at age 14 years.
Conclusions: Early high-dose treatment and optimal substitution during childhood is important, but subtle IQ deficits remain. Severity, suggesting pre- and perinatal cerebral injury, and SES strongly impacts on intellectual outcome. Therefore close surveillance and early detection of developmental delay is a demand in children with CH.
|Publications / Publikationen||Dimitropoulos A, Molinari L, Etter K, Torresani T, Lang-Muritano M, Largo RH, Latal B. (2009) Children with Congenital Hypothyroidism: Long-term Intellectual Outcome after Early High-Dose Treatment. In press Pediatric Research|
|Project leadership and contacts /
Projektleitung und Kontakte
|Funding source(s) /
|SNF (Personen- und Projektförderung)
|Duration of Project / Projektdauer||Mar 2005 to Dec 2008|