Puberty, statural growth, and growth hormone release in children with cerebral palsy

Objective: Children with cerebral palsy (CP) are smaller than normally growing children. The association between the growth hormone (GH) axis and growth in children with CP during puberty is unknown. We compared growth and markers of the GH axis in pre-pubertal and pubertal children with moderate to severe CP and without CP over a three-year period. Study design: Twenty children with CP, ages 6-18, Gross Motor Function Classification System levels III-V, were compared to a group of sixty-three normally growing children of similar age. Anthropometry, Tanner stage, bone age, and laboratory analyses were performed every six months for three years. Laboratory values included spontaneous overnight GH release, fasting IGF-1 and IGFBP-3. Repeated measures models were used to evaluate interactions among Tanner stage and group (children with CP vs. reference children), taking into account gender, age, and nutritional status. Results: Children with CP grew more slowly than those without CP at all Tanner stages (p < 0.01). Patterns of IGF-1 and GH secretion in children with CP were similar to those of the reference group; however, the concentrations of IGF-1 (p < 0.01) and GH (p < 0.01) were lower in girls with CP, with a similar trend for boys (p = 0.10 and 0.14, respectively). Conclusions: Diminished circulating IGF-1 and GH concentrations may explain the differences in growth between the two groups.