Backround: Male hypogonadism is associated with an increased incidence of cardiovascular risk factors and approximately 25% of males suffering with coronary heart disease are hypogonadal. Few studies have assessed the impact of testosterone therapy on vascular function in hypogonadal individuals and none have investigated the weekly impact of gradually reducing testosterone concentrations on vasculature.
Patients and Methods: 10 hypogonadal subjects (6 with 10 hypogonadism, 4 with 20 hypogonadism) were studied on a weekly basis throughout a monthly treatment cycle with intra-muscular Sustanon 250. Each subject acted as their own control. Subjects with known cardiovascular risk factors, AF and hypopituitarism were excluded. Lipid profiles, glucose, insulin and haematocrit were measured in each subject in addition to sex hormone profiles. Arterial stiffness and central arterial compliance was analysed with pulse wave analysis (Sphygmocor apparatus) using inhaled salbutamol and GTN as surrogate markers to assess endothelial dependent and independent vasodilatation respectively. Further assessment of endothelial function was determined using flow mediated dilatation in the brachial artery.
Results: FMD and the Augmentation Index were unaltered by the gradual reductions in testosterone concentrations (wk 1 35.98±22.21 nmol/l vs wk 2 16.05±8.65 nmol/l, wk 3 11.21±6.14 nmol/l, wk 4 6.32±2.91 nmol/l, P<0.0005) throughout a monthly treatment cycle with Sustanon. Despite this, FMD in hypogonadal subjects was impaired (8.9±3.0%), compared with previous studies on healthy eugonadal males.
Conclusion: Hypogonadal males have impaired vascular reactivity which is unaffected by weekly fluctuation in testosterone concentrations.
01 - 05 Apr 2006
European Society of Endocrinology