Insulin sensitivity in growth hormone-deficient children: influence of replacement treatment.
OBJECTIVE
In adults, excessive GH secretion may lead to secondary diabetes mellitus, while prolonged GH treatment may accelerate the onset of type 2 diabetes mellitus in predisposed children. The aim of the study was to evaluate insulin sensitivity (IS) and glucose tolerance (GT) in a group of GH-deficient children treated with GH for a period of 6 years.


METHODS
One hundred and twenty-eight children (40 females, 88 males) were included in the study. At the beginning of treatment chronological age was 8.9 +/- 3.2 years, height standard deviation score (SDS) -2.43 +/- 0.90 and body mass index (BMI) SDS 0.18 +/- 1.60. At the end of the study chronological age was 13.0 +/- 2.9 years, height SDS -1.24 +/- 1.27 and BMI SDS 0.23 +/- 1.54. GH was administered at a mean weekly dosage of 0.3 mg/kg, injected subcutaneously over 6-7 days. GT was assessed according to the criteria of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. IS was evaluated with the quantitative insulin sensitivity check index (QUICKI).


RESULTS
No cases of impaired GT or diabetes were recorded during the follow-up period. IS, already lower than in controls before starting treatment with GH, decreased significantly during the first year of therapy (QUICKI: 0.346 +/- 0.033 vs. 0.355 +/- 0.044, P < 0.05), with no further decrease in the following years. No correlation was found between QUICKI, BMI, years of treatment and onset of puberty.


CONCLUSIONS
GH treatment in GH-deficient children does not lead to an impaired GT or type 2 diabetes mellitus, although it does significantly decrease IS.
Radetti
Giorgio
G
Department of Paediatrics, Regional Hospital of Bolzano, Italy. giorgio.radetti@asbz.it
Pasquino
Bruno
B
Gottardi
Elena
E
Contadin
Isabella Boscolo
IB
Rigon
Franco
F
Aimaretti
Gianluca
G
D001786:Blood Glucose / Q000032:analysis; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D005260:Female; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000172:deficiency* / Q000627:therapeutic use*; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male
D001786:Blood Glucose; D007328:Insulin; D013006:Growth Hormone