[The influence of long-term growth hormone replacement therapy on body composition, bone tissue and some metabolic parameters in adults with growth hormone deficiency]

A syndrome of growth hormone deficiency in adults (GHDA) is a syndrome characterised by metabolic deviations, body composition abnormalities, fatigue, decreased quality of life and some cardiovascular changes. The aim of the study was to assess the influence of the growth hormone (GH) replacement therapy on body composition, bone changes, serum lipids levels and some parameters of sugar metabolism in the course of 7-year monitoring. We followed 34 individuals of mean age of 41.73 +/- 2.49 years (mean +/- SE). Severe deficiency of GH was demonstrated by performing stimulation insulin tolerance test. Duration of treatment was 4.13 +/- 0.36 years (mean +/- SE). Patients were examined before the initiation of replacement therapy, after 6 months and further in yearly visits. To determine a statistical level of significance in individual parameters we compared initial baseline status (before drug administration) with the status in individual time intervals. The body composition was examined by anthropometric methods, bioelectric impedance and by densitometry, bone changes were examined by means of DEXA. There were no statistically significant changes of weight, but the waist circumference significantly decreased (p < 0.05), as well as the sum of skinfold thickness (p < 0.05) within the whole treatment period. The percentage of body fat mass measured by the BIA method was significantly changed after the period of 3 years (p < 0.05). Upon the densitometrical measurement of the body composition a significant decrease in kilograms of body fat mass (FM) occurred in the first year of the treatment (p < 0.05) and an increase in lean body mass (LBM) in kilograms during our complete monitoring (p < 0.05). A statistically significant increase in bone density was found in the whole-body BMD and BMC after the first year of the treatment. In the examination of peripheral bone changes a statistically significant increase in BMD occurred (expressed as a Z score) in the area of proximal femur after the first year and collum femoris after three years (p < 0.05), there was a significant increase in BMD of the lumbar spine already after one year of the treatment (p < 0.05) and changes were significant also in further four years. There were found no statistically significant changes related to the sugar metabolism. In the field of lipid metabolism a decrease of total and LDL cholesterol occurred already after a half of the year of the treatment (p < 0.05), changes were significant also in further four years. HDL cholesterol levels have had a progressive tendency, but they were not statistically significant. Positive changes of body composition, an increase in bone density and a decrease of total and LDL cholesterol were demonstrated in the course of the growth hormone replacement therapy.