Serum insulin like growth factor-1 and growth hormone levels in newborn babies with hypoxic ischemic encephalopathy

ABSTRACT Serum Insulin like growth factor-1 and Growth hormone Levels In Newborn Babies with Hypoxic Ischemic Encephalopathy Hypoxic ischemic encephalopathy is an important problem in neonatal period, especially in developing countries where prenatal care is inefficient. It is a leading cause of morbidity and mortality in these countries such as ours, new treatment methods should be sought after in addition to supportive therapy. In a study, it has been showed that significant changes have been observed in insulin like growth factor-1 (IGF-1) in asphyxic rat and that IGF-1 has taken endogen neuroprotective role in asphyxia. The aim of this study is to find out whether the levels of the serum IGF-1 in the babies with hypoxic ischemic encephalopathy. In this study, 18 babies with hypoxic ischemic encephalopathy and healthy 19 babies to form patient and control groups respectively were included in the study at the Çukurova University, Medical Faculty, Division of Neonatology, Neonatal Intensive Care Unit. The cases with HIE were staged according to the Sarnat and Sarnat classification. In both study and control groups, birth weights and gestational ages were similar. The serum IGF-1 levels of babies with HIE were measured in the first 12-24 hours of birth and again in the 5th and 10th days. Blood samples for other measurements as well as IGF- I were taken in the first 12-24 hours of birth for the control group. Serum IGF-1 and growth hormone (GH) levels were measured quantitativly with lmmunoradiometrique assay method and serum cortisole level was measured with Chemiluminescence method. The serum levels of IGF-1 obtained from the babies with HIE in the first 12-24 hours and 10th day were 78.5+27.9 ng/ml and 72.2±36.8 ng/ml respectively and the values for the control group were 121.5±50.4 ng/ml in the first 12-24 hours and 133.1±34.4 ng/ml for the 10th day. The IGF-1 levels of the study group measured in the first 12-24 hours and 10th day were lower than the levels measured in the control group and the difference between these levels are statistically significant (p=0.02, p<0.001). The GH levels of the babies in the study group in the first 12-24 hours were higher than the levels obtained in the control group and there was a statistically significant difference (p=0.005). There wasn't any statistically significant difference in the cortisole levels of the babies in the first 12-24 hours in the both groups(p>0.05). When the IGF-1 levels of cases with HIE were analysed according to stages, there was astatitically significant difference between Stage I and Stage II (p<0.05) but there weren't any statitically significant differences between the levels in the stage I and stage III and also stage II and stage III(p>0.05). As a conclusion, our study has shown that newborn babies with HIE had low serum IGF-1 levels and high serum GH levels. For the pathophysiology of these changes to be understood further research in needed. Therapies focusing on the IGF-1 system may be rewarding in the future and are needed for detailed research. Key words: Hypoxic ischemic encephalopathy, IGF-1, GH VIII