Klinefelter syndrome (KS) is the most common sex chromosome disorder affecting 1:600 men.
We know from previous clinical and epidemiological studies that men suffering from KS have an increased risk of diabetes and an increased risk of dying from diabetes, but the reasons for the increased risk are unknown.
Seventy KS patients and 71 age-matched men participated in a study on body composition, measures of sex hormones, insulin sensitivity, blood pressure and various risk factors for ischemic cardiac disease.
Almost half of the KS patients fulfilled the NCEP/ATPIII criteria for the metabolic syndrome, whereas it was true for only 10% of the control group. Curiously, there was no difference in blood pressure between the two groups. Plasma lipids including LDL cholesterol were increased, while HDL cholesterol was decreased. Significantly more KS subjects had elevated fasting plasma insulin levels and calculation of insulin sensitivity using HOMA2 modelling showed a significant decrease in insulin sensitivity. KS subjects had excessive amounts of body fat and especially truncal fat. Multivariate analysis showed that the truncal obesity was the major determinant of both metabolic syndrome and decreased insulin sensitivity, even when controlled for testosterone and other androgens.
KS patients had normal values of adiponectin despite increased amount of body fat. This unexpected finding may in part explain the normal blood pressure, contrary to what would be expected from all the increased risk factors for ischemic cardiac disease. The potential cardioprotective effect of hypogonadism or the syndrome per se is reflected by a significant decreased mortality from ischemic cardiac disease found in a recent epidemiological study.
03 - 07 May 2008
European Society of Endocrinology