Use of Sildenafil (Viagra) in Diabetic Men With Erectile Dysfunction: the Impact on Blood Vessels

The Use and Efficacy of Sildenafil in Diabetic Men With Erectile Dysfunction: the Impact on Endothelial Function, a Pilot Feasibility Study

To evaluate the impact of nightly sildenafil vs placebo use on diabetic men with and without proven endothelial dysfunction and coexisting erectile concerns. To determine if chronic sildenafil use compared to placebo positively impacts endothelial function among a cohort of diabetic mend with erectile dysfunction To assess the salvage rate of sildenafil - failures who demonstrate improved response rates over time with chronic use To assess if microalbuminuria predicts flow-mediated dilation (FMD) response To measure and identify if other patient specific characteristics predict for sildenafil erectile response and flow-mediated dilatation (FMD) response over time (patient specifics; blood pressure, HBA1c, weight, BMI, age IIEF score at baseline)

60 type II diabetic men with erectile dysfunction will be enrolled in this trial, evaluated over a 12 week period. Randomization into one of two arms (placebo, daily sildenafil 50mg) will be a doubly blinded. Subjects will be followed by IIEF, diaries and brachial forearm medial dilatation duplex scans, urinary microalbuminuria and serum chemistry. Study time-points are at baseline, 6 and 12 weeks. Study participants will be instructed to use the study medication at the specified frequency but will be allowed flexibility to suit their erectile needs.

Determine if PDE5 use over 12 week period in ED diabetic men improves endothelial function as measured by FMD of the brachial artery, as compared to placebo; Assess treatment response to sildenafil over a 12 week period of exposure compared to placebo.

Inclusion Criteria: Age > 18 years of age Type 2 diabetes > 6 months in duration. Men using oral hypoglycemic agents and /or insulin will be permitted into the trial. Stable hetero- sexual relationship for > 6 months IIEF score at baseline <21· Agrees to sign informed consent Exclusion Criteria: Known hypersensitivity to sildenafil Use of nitrates Use of anti-coagulants History of significant heart disease, +/or myocardial infarction within last 6 months Unable to understand or unwilling to sign informed consent Concomitant use of erectogenic agent during study

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