Bone density and body composition in children with growth hormone insensitivity syndrome receiving recombinant IGF-I

• Published in: Clinical endocrinology (Oxford) Vol. 59; no. 4; pp. 487 - 491
• Main Authors: Shaw, N. J., Fraser, N. C., Rose, S., Crabtree, N. J., Boivin, C. M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-10-2003; Blackwell; Wiley Subscription Services, Inc
• Subjects: Absorptiometry, Photon; Adipose Tissue - drug effects; Biological and medical sciences; Body Composition - drug effects; Body Height - drug effects; Bone Density - drug effects; Child; Endocrinopathies; Fundamental and applied biological sciences. Psychology; Growth Disorders - drug therapy; Growth Disorders - physiopathology; Humans; Insulin-Like Growth Factor I - deficiency; Insulin-Like Growth Factor I - therapeutic use; Longitudinal Studies; Male; Medical sciences; Prospective Studies; Recombinant Proteins - therapeutic use; Skinfold Thickness; Syndrome; Vertebrates: endocrinology; Human; Osteoarticular system; Laron dwarfism; Bone; Recombinant protein; Insulin like growth factor 1; Density; Child; Body composition; Endocrinology
• ISSN: 0300-0664; 1365-2265
• DOI: 10.1046/j.1365-2265.2003.01875.x

Summary
objective  There are few reports of the metabolic action of insulin‐like growth factor 1 (IGF‐I) in vivo. Growth hormone insensitivity syndrome is a good model to examine the effects of IGF‐I deficiency. This study was designed to assess body composition and bone density in children with growth hormone insensitivity syndrome before and after receiving treatment with recombinant IGF‐I.
design  A prospective longitudinal study.
patients  Four prepubertal boys age 6·1–9·8 years with short stature due to growth hormone insensitivity syndrome.
measurements  Assessment of body fat by skinfold thickness measurements and dual energy X‐ray absorptiometry (DXA) was made during the first 6 months of recombinant IGF‐I treatment. Assessment of lumbar spine bone density by DXA was performed prior to IGF‐I treatment and during the subsequent five years.
results  Each child showed a significant reduction in fat mass (0·26–1·22 kg) after 6 weeks of IGF‐I treatment. Bone density prior to treatment was reduced in comparison to age‐matched controls but calculated volumetric bone density was within the normal range. Volumetric bone density progressively improved over the 5‐year treatment period.
conclusions  Children with growth hormone insensitivity syndrome exhibit a metabolic response to IGF‐I within 6 weeks analogous to that seen in GH‐deficient children receiving GH. Bone density when corrected for body size is within normal limits and demonstrates a response to IGF‐I, confirming the anabolic action on bone.