Effects of Sildenafil in Resistant Hypertensives and Genetic Polymorphism

NCT01392638 | Completed

• 2 other identifiers: CAAE-0758.0.146.000-09FAPESP
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

Sildenafil citrate slightly reduces blood pressure in treated hypertensives patients. However, it is unknown if the simultaneous use of sildenafil plus, at least, 3 classes of antihypertensive agents in patients with resistant arterial hypertension may have a synergic effect on the patients blood pressure. Moreover, sildenafil improves the endogen nitric oxide effects. The nitric oxide is an important signaling molecule in the body that contributes to vessel homeostasis by inhibiting vascular smooth muscle contraction and growth. Hypertension often impaired NO pathways. Nitric oxide is produced by an enzyme, called nitric oxide synthase (NOS3), that show some genetics variants, which means that this enzyme can be different from person to person. Therefore, the objective of the present study is to examine the influence of a genetic variant (known to affect NOS3 levels) in sildenafil acute effects on hemodynamic and cardiovascular function. The investigators hypothesis is that individuals with the genetic variant associated to higher levels of NOS3 will have more benefits from sildenafil treatment.

Conditions

Hypertension

Keywords

Sildenafil; Nitric oxide synthase; Polymorphism; Hemodynamics

Outcome Measures

Primary Outcomes (1)

• Cardiac Output, total peripheral resistance, mean arterial pressure

  Hemodynamic measures each 30 minutes

  Each 30 minutes

Secondary Outcomes (1)

• Left ventricular diastolic function parameters, endothelial function

  Pre- and post-sildenafil accumulated doses

Study Arms (2)

sugar pill

PLACEBO COMPARATOR

Intervention: sugar pill

Other: sugar pill

sildenafil

ACTIVE COMPARATOR

Intervention: sildenafil citrate

Drug: sildenafil

Interventions

sugar pill OTHER

Sugar pills: 37.5, 50.0, and 100.0 mg each 30 minutes.

Also known as: No brand name.

sugar pill

sildenafil DRUG

Sildenafil pills: 37.5, 50.0, and 100.0 mg each 30 minutes.

Also known as: Viagra, Pfizzer Lab., USA

sildenafil

Eligibility Criteria

• Age: 35 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• resistant hypertensive (according to Resistant Hypertension - AHA Statement - 2008);
• compliance with antihypertensive treatment;
• age \>35 years;
• diastolic dysfunction

You may not qualify if:

• valvulopathy
• decompensated heart failure
• important cardiac arrhythmias
• nephropathy
• hepatopathy
• autoimmune disease
• tabagism
• decompensated diabetes
• uncontrolled dislipidemia

Sponsors & Collaborators

• University of Campinas, Brazil: lead
• Fundação de Amparo à Pesquisa do Estado de São Paulo: collaborator

Study Sites (1)

Laboratory of Cardiovascular Pharmacology - FCM - Unicamp

Campinas, São Paulo, Brazil

Location

MeSH Terms

Conditions

Hypertension

Interventions

Sugars; Sildenafil Citrate

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Carbohydrates; Sulfonamides; Amides; Organic Chemicals; Sulfones; Sulfur Compounds; Piperazines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Officials

• Heitor Moreno, PhD

  Faculty of Medical Sciences - Unicamp

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD. PhD

Study Record Dates

• First Submitted: January 25, 2011
• First Posted: July 12, 2011
• Study Start: July 1, 2010
• Primary Completion: July 1, 2012
• Study Completion: September 1, 2012
• Last Updated: October 30, 2012

Record last verified: 2012-10

Locations

BR (1)