Androgen deprivation therapy reversibly increases endothelium-dependent vasodilation in men with prostate cancer

Background-androgen deprivation therapy (adt) is a standard treatment for patients with aggressive prostate cancer. althoughadt improves survival,it increases the risk of diabetes. emerging evidence suggests that adt increases adverse cardiovascularevents as early as 3 months after initiation in patients with cardiovascular disease,but the mechanism is unknown. wehypothesized that adt may impair endothelium-dependent vasodilation due to increases in lipids and insulin resistance and mayprovide a link for heightened cardiovascular risk in this population.methods and results-we prospectively evaluated conduit artery endothelium-dependent and -independent vasodilation,lipids,and insulin resistance in 16 consecutively treated men (mean age 66±7 years; 25% with diabetes) with prostate cancer before andafter 3 months of adt. high-resolution b-mode ultrasound was used to assess flow-mediated (endothelium-dependent) andnitroglycerine-mediated (endothelium-independent) brachial artery vasodilation. adt significantly increased insulin resistance,totalcholesterol,hdl,and ldl. endothelium-dependent vasodilation was greater at 3 months than at baseline (10.8% [interquartilerange: 7.7% to 14.6%] versus 8.9% [interquartile range: 4.0% to 12.6%],respectively; p=0.046,allometric p=0.037). nitroglycerinemediatedvasodilation did not change from baseline (p>0.2). the subset of participants on adt for 6 months returned forreevaluation at 1 year. in this group,endothelium-dependent vasodilation increased from baseline to 3 months and returned tobaseline 6 months after adt withdrawal (9.4% [interquartile range: 6.9% to 10.9%],11.6% [interquartile range: 7.9% to 15.2%],and9.0% [interquartile range: 5.1% to 12.5%],respectively; p=0.05).conclusions-in contrast to our expectation,adt improved endothelium-dependent vasodilation and its cessation returnedendothelium-dependent vasodilation to baseline. determining the mechanism of this change requires further investigation. © 2015 the authors.