Related Experiment Videos
Normalized growth velocity in children with Down's syndrome during growth hormone therapy
G Annerén1, J Gustafsson, V R Sara
1Department of Clinical Genetics, University Hospital, Uppsala, Sweden.
Insights
Growth hormone therapy significantly improves height in children with Down syndrome (DS). Treatment initiated in infancy leads to sustained height gains, with head circumference showing less response, suggesting microcephaly in DS.
Area of Science:
- Pediatrics
- Endocrinology
- Genetics
Background:
- Children with Down syndrome (DS) exhibit reduced growth velocity between 6 months and 3 years.
- Growth hormone (GH) plays a crucial role in regulating growth during this critical period.
- Growth retardation in DS becomes pronounced as GH starts to regulate growth.
Purpose of the Study:
- To evaluate the long-term effects of GH therapy on growth in children with DS.
- To assess the impact of GH therapy on height and head circumference in infants and young children with DS.
Main Methods:
- Longitudinal study of 16 children with DS treated with Genotropin (GH).
- Treatment initiated between 6-9 months of age at a dosage of 0.1 U/kg/day.
- Measurements of height and head circumference standard deviation scores (SDS) recorded at 12, 24, and 30 months.
Main Results:
- Mean height SDS improved from -1.8 to -1.1 after 12 months, -0.9 after 24 months, and -0.9 after 30 months.
- Mean head circumference SDS remained relatively stable, showing minimal improvement from -1.2 to -1.1.
- Children's height reached the 95th percentile for DS growth charts after 24 months of treatment.
Conclusions:
- GH therapy effectively enhances height in children with Down syndrome.
- The therapy leads to sustained height growth, aligning with healthy children's growth rates after the first year.
- Limited head circumference response suggests microcephaly is a significant factor in DS head size, beyond general growth retardation.
Abstract:
Between 6 months and 3 years of age, growth velocity in children with Down's syndrome (DS) is markedly reduced in comparison to that of healthy children. However, after 3 years of age, it is almost normal. Thus, growth retardation becomes pronounced during the period when growth hormone (GH) starts to regulate growth. The present authors report the long-term effects of GH-therapy in 16 children with DS, who are being treated for 3 years from the age of 6-9 months. The treatment, Genotropin, 0.1 U kg-1 BW day-1, was started at a mean age of 7.4 (6-9) months. The results after 12 (n = 16), 24 (n = 12) and 30 (n = 8) months are presented. The mean height standard deviation score, SDS (range; Swedish standard), before therapy was -1.8 (-0.5 to -3.1) and the mean head circumference was -1.2 (-0.4 to -3.5). After 12, 24 and 30 months, the mean height SDS were -1.1 (-0.8 to -1.9), -0.9 (0 to -1.5) and -0.9 (0.1 to -1.5) and the mean head circumference SDS were -1.1 (0 to -2.5), -1.1 (0 to -2.2) and -1.2 (-0.5 to -2.0), respectively. During hGH-treatment, the children with DS thus gained height during the first year, and then followed the growth rate of healthy Swedish children. When compared to growth charts for children with DS the mean height of these children started at the fiftieth centile and reached the ninety-fifth centile after 24 months of treatment. Head circumference only slightly increased during the therapy, and not to the same extent as height. This indicates that small head circumference in DS is not only an effect of growth retardation, but also due to microcephaly.