Abstract 99: The Effect of Androgen Deprivation Therapy on Conduit Artery Endothelial Function in Men with Prostate Cancer
Introduction Androgen deprivation therapy (ADT) is a standard treatment for patients with aggressive prostate cancer. While ADT improves cancer-specific and overall survival, it can increases insulin resistance and the risk of diabetes. Emerging evidence suggests that ADT also increases the incidence of adverse cardiovascular events in patients with cardiovascular disease, but the exact mechanism is unknown.
Hypothesis We hypothesized that ADT may impair endothelial function due to increases in insulin resistance and provide a mechanism for heightened cardiovascular risk in this population.
Methods and Results We prospectively evaluated conduit artery function in 10 consecutive men (mean age 65 ± 7 years; 30% with diabetes) with prostate cancer before and 3 months after initiation of ADT. High-resolution B-mode ultrasound was used to assess flow-mediated (endothelium-dependent) and nitroglycerine-mediated (endothelium-independent) brachial artery vasodilation. Endothelium-dependent vasodilation was greater at 3 months compared with baseline (11.9 ± 1.7% vs. 9.23 ± 1.8%, p = 0.002). There was no significant change in resting arterial diameter, reactive hyperemic stimulus, mean arterial pressure, nor heart rate between study conditions. Nitroglycerine-mediated, endothelium-independent vasodilation did not change from baseline (18.3 ± 3.55%) to the three month visit (19.7 ± 2.40%), p = 0.466). Markers of insulin resistance will be available at the time of the meeting.
Conclusions In contrast to our expectation, ADT improves endothelial function. This suggests that the physiological mechanism linking ADT with increased cardiovascular events is not likely regulated by the vascular endothelium. Moreover, this mechanism of insulin resistance may be beneficial to endothelial function.
- © 2013 by American Heart Association, Inc.