High serum levels of growth hormone (GH) and insulin-like growth factor-I (IGF-I) during high-dose GH treatment in short children born small for gestational age.
BACKGROUND
Epidemiological studies have indicated that high serum levels of GH and IGF-I are associated with long-term risks.


OBJECTIVE
The objective of the study was to evaluate the changes in serum levels of GH during overnight profiles, IGF-I, and IGF binding protein 3 (IGFBP-3) in short small for gestational age (SGA) children during GH treatment with two doses.


METHODS
Thirty-six prepubertal short SGA children were the subjects of this study.


METHODS
Subjects received 1 (group A) or 2 (group B) mg GH/m(2).d.


METHODS
At baseline and after 6 months of GH treatment, overnight GH profiles were performed, and serum IGF-I and IGFBP-3 levels were measured.


RESULTS
After 6 months, group B had significantly higher GH levels during the profile (mean, maximum, and area under the curve above zero line) than group A (P < 0.009). In group B, maximum GH levels increased from 43.9-161 mU/liter (P < 0.0002), and in group A, from 57.2-104 mU/liter (P = 0.002). During the profile (i.e. 12 h per day), children of group B had mean GH levels of 64.4 vs. 34.8 mU/liter in group A (P = 0.001). The IGF-I and IGF-I to IGFBP-3 ratio sd scores increased significantly in both groups, but were higher in group B than A [1.5 vs. 0.2 (P = 0.002) and 1.4 vs. 0.3 (P = 0.007), respectively]. In group B, 74% of the children had IGF-I levels in the highest quintile during GH treatment compared with 19% in group A.


CONCLUSIONS
Our study shows that high-dose GH treatment in short SGA children results in high serum GH and IGF-I levels in most children. We recommend monitoring IGF-I levels during GH therapy to ensure that these remain within the normal range.
van Dijk
Marije
M
Department of Pediatrics, Division of Endocrinology, Erasmus University Medical Center, Sophia Children's Hospital sk-0152, P.O. Box 2060, 3000 CB Rotterdam, The Netherlands. m.vandijk.1@erasmusmc.nl
Mulder
Paul
P
Houdijk
Mieke
M
Mulder
Jaap
J
Noordam
Kees
K
Odink
Roelof J
RJ
Rongen-Westerlaken
Ciska
C
Voorhoeve
Paul
P
Waelkens
Johan
J
Stokvis-Brantsma
Jet
J
Hokken-Koelega
Anita
A
D019540:Area Under Curve; D001827:Body Height / Q000502:physiology*; D002648:Child; D005260:Female; D006128:Growth / Q000187:drug effects / Q000502:physiology; D013006:Growth Hormone / Q000627:therapeutic use*; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male
D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone