Effects of Sildenafil on Penile Vascular Function in Hypertensive Men With Erectile Dysfunction
Condition: Arterial Hypertension; Erectile Dysfunction
MeSH terms: Erectile Dysfunction; Hypertension
Study type: Interventional
Phase: Phase 4

Summary: 
      The study will evaluate the effects of a chronic 30-day treatment with sildenafil citrate on
      penile and systemic microvascular function as well as in blood pressure.

      A control group of normotensive age-matched healthy subjects will serve as a comparator group
      for normal penile and systemic microvascular function.
    

Detailed description: 
      Vasculogenic erectile dysfunction (ED) is a highly prevalent health problem that is directly
      related with increased cardiovascular risk. In this context, phosphodiesterase type 5
      inhibitors (PDE5 inhibitors) are indicated in the treatment of ED because these drugs
      increase bioavailability of the endothelial-dependent potent vasodilator nitric oxide. Thus,
      these drugs could also induce a reduction in arterial pressure and improve microvascular
      endothelial function in hypertensive patients.

      The primary aim of the study is to investigate the acute and chronic effects of sildenafil
      citrate (®Viagra) on penile and systemic microvascular function of hypertensive patients
      presenting with ED. The secondary aim is to evaluate the effects of the treatment on arterial
      pressure.

      The study design is a prospective 2 x 2 cross-over, randomized, double blind clinical trial
      that will include 75 sexually active hypertensive men (age between 50-70 years) under
      anti-hypertensive treatment (arterial pressure < 160/100 mmHg) presenting with ED. Erectile
      function will be evaluated using the International Index of Erectile Function (IIEF-5)
      questionnaire. Patients with non-vasculogenic ED or diabetes will be excluded from the study.
      Forty-five age-matched healthy subjects will be included as a comparator group.

      The evaluation of systemic microvascular function will be performed in the skin of the
      forearm and penile microvascular function in the skin of the base of the penis using the
      non-invasive methodology of laser speckle flowmetry coupled to cutaneous iontophoresis of a
      vasodilator (acetylcholine).

      In the acute protocol, microvascular evaluation will be carried out before and one hour after
      the oral administration of 100 mg of sildenafil citrate. In the chronic protocol, only
      hypertensive men will be randomized to receive either or placebo sildenafil 50 mg twice daily
      for 30 days. After a 30-day washout period the patients will receive the complementary
      treatment.

      The evaluation of penile and systemic microvascular function, as well as ambulatory blood
      pressure monitoring, will be performed before randomization and in the end of each treatment
      period.
    

Intervention name(s): sildenafil citrate; comparator group
Intervention type(s): Drug; Other
Intervention description(s): the hypertensive patients with erectile dysfunction will be treated with sildenafil citrate (100 mg daily) or placebo (crossover design); Normotensive individuals age-matched to the hypertensive patients will receive only a single dose of sildenafil citrate (100 mg) - acute protocol. Penile and systemic microvascular function will be evaluated before and one hour after sildenafil administration.
Other intervention name(s): Viagra
Intervention MeSH terms: Sildenafil Citrate
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: hypertension; endothelial dysfunction; erectile dysfunction; sildenafil