Increased Carotid Intima-media Thickness and Its Association with Carbohydrate Metabolism and Adipocytokines in Children Treated with Recombinant Growth Hormone

INTRODUCTION: Reports on the association between growth hormone (GH) therapy and cardiovascular risk factors in children are limited. This study aimed to evaluate carotid intima-media thickness (cIMT) in children treated with recombinant human GH (rhGH) and assess the effects of rhGH therapy and changes in serum carbohydrate metabolism, lipid profile and adipocytokines on cIMT.
METHODS: Seventy-one isolated idiopathic GH deficiency (GHD) children and 44 age- and sex-matched healthy controls were enrolled in this study. The study group was divided into two subgroups according to insulin resistance (IR) on oral glucose tolerance tests. Insulin secretion [homeostatic model assessment (HOMA) B, total insulin] and sensitivity (HOMA-IR, QUICKI, Matsuda) indices were calculated. cIMT was measured and the standard deviation scores (SDS) were calculated. Associations between cIMT-SDS and insulin secretion and sensitivity indices, serum lipid levels, adipocytokines (leptin, resistin, ghrelin), and other rhGH treatment-related factors were evaluated.
RESULTS: cIMT-SDS was increased in GHD children treated with rhGH compared to the controls [0.02 (2.27) vs. -1.01 (1.63), p=0.003]. cIMT-SDS did not differ between those children on rhGH treatment with or without IR. High cIMT-SDS was significantly associated with higher serum ghrelin levels and lower serum high density lipoprotein (HDL) levels (β=0.491, p=0.001 and β=-0.027, p=0.017), but not with BMI-SDS, blood pressure, insulin secretion and sensitivity indices, or the dose and duration of rhGH therapy.
DISCUSSION AND CONCLUSION: Our findings showed that GHD children treated with rhGH have increased cIMT. Alterations in carbohydrate metabolism were not associated with cIMT in children treated with rhGH. GH therapy per se appears to be associated with this increased cIMT but causality should be elucidated in further studies. cIMT also appears to be associated with higher ghrelin and lower HDL levels.