Effect of 5 Years of GH Replacement on Atherosclerosis

This is an observational,5-yr prospective, controlled study. At study entry, all subjects underwent serum assay of IGF-I, systolic and diastolic blood pressure (SBP, DBP) measurement, total-, and HDL-cholesterol, triglycerides, glucose, and insulin level after an overnight fasting, and common carotid arteries ultrasonography. The oral glucose load (oGTT) was performed by measuring blood glucose every 30 minutes for 2 hours after the oral administration of 75 g of glucose diluted in 250 ml of saline solution. The conversion factors (mg/dl to mmol/l) for lipids and glucose were as follows: cholesterol 0.02586, triglycerides 0.01129, and glucose 0.05551. According with previous studies (13,19-21) blood pressure was measured at the right arm, with the subjects in relaxed sitting position. The average of six measurements (three taken by each of two examiners, in the same day, between 8.00-9.00 in the morning) with a mercury sphygmomanometer was used in all analysis. In the patients, all parameters and carotid ultrasonography were re-evaluated after 12, 24, 36, 48 and 60 months while in controls they were re-evaluated after 60 months. At study entry and at study end, in all of the patients and controls the prevalence of insulin-resistance syndrome (IRS) was evaluated according with the American College of Endocrinology (14) based on the presence of at least two criteria of the following: triglycerides levels ≥1.7 mmol/liter, HDL-cholesterol levels ≤1.0 mmol/liter, blood pressure above 130/85 mmHg, fasting glucose between 6.1 and 7 mmol/liter or 2 hr after oGTT between 7.7 and 11.1 mmol/liter.