Sildenafil and Exercise Capacity in Hypertension

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00599235
Recruitment Status : Completed
First Posted : January 23, 2008
Last Update Posted : April 8, 2010
Information provided by:
University of Edinburgh

Brief Summary:
Hypertension (persistently elevated blood pressure) is a major risk factor for heart disease and stroke. Hypertensive individuals show a reduced exercise capacity, which is present from a very early stage and contributes to their increased cardiovascular risk. Sildenafil belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors, and it works by enhancing the effects of nitric oxide, a substance that dilates blood vessels and increases blood flow. We hypothesize that sildenafil, because of its effect on nitric oxide and blood flow, will improve exercise capacity in hypertensive patients. Therefore, the main aim of the study is to investigate the effects of PDE5 inhibition on exercise capacity and vascular function in hypertension, and to compare these effects in hypertensive patients and healthy controls.

Condition or disease Intervention/treatment Phase
Hypertension Drug: sildenafil Drug: hydralazine Drug: placebo Not Applicable

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 30 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Official Title: Effects of the Selective Phosphodiesterase Type 5 Inhibitor Sildenafil Citrate on Exercise Capacity and Vascular Function in Hypertensive Subjects
Study Start Date : March 2007
Actual Primary Completion Date : May 2008
Actual Study Completion Date : August 2008

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arm Intervention/treatment
Experimental: 1 Drug: sildenafil
50mg 3 times daily for 7 days
Other Name: Viagra
Drug: hydralazine
25mg 3 times daily for 7 days
Drug: placebo
3 times daily for 7 days
Active Comparator: 2 Drug: sildenafil
50mg 3 times daily for 7 days
Other Name: Viagra
Drug: hydralazine
25mg 3 times daily for 7 days
Drug: placebo
3 times daily for 7 days

Primary Outcome Measures :
  1. Peak oxygen uptake (VO2) during exercise [ Time Frame: 1 week of treatment ]

Secondary Outcome Measures :
  1. Exercise systolic blood pressure [ Time Frame: Maximal exercise ]
  2. Pulse wave velocity and pulse wave analysis [ Time Frame: Before and after maximal exercise ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Male (age range: 18 - 70 years)
  • Appropriate blood pressure range
  • Hypertensive - Systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg
  • Controls - Systolic BP <140 mmHg and diastolic BP <90mmHg
  • Written informed consent

Exclusion Criteria:

  • Female
  • History of coronary artery, cerebrovascular or peripheral vascular disease within the last 6 months
  • Total cholesterol >6.5 mmol/L
  • Current alcohol abuse
  • Diabetes mellitus
  • Asthma
  • Taking any anti-hypertensive, vasoactive or endothelial function modifying drugs which cannot be withdrawn for the purpose of the study
  • ECG evidence of clinically significant arrhythmia or cardiac ischaemia
  • Clinically significant abnormality on screening blood test
  • Contraindication to strenuous exercise
  • Current involvement in other research projects
  • Other clinically relevant conditions
  • Lack of written informed consent

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00599235

United Kingdom
University of Edinburgh - Western General Hospital
Edinburgh, United Kingdom, EH4 2XU
Sponsors and Collaborators
University of Edinburgh
Principal Investigator: Teresa M Attinà, MD University of Edinburgh
Study Director: David J Webb, MD University of Edinburgh

Responsible Party: Marise Bucukoglu, University of Edinburgh Identifier: NCT00599235     History of Changes
Other Study ID Numbers: LREC/2004/4/13
First Posted: January 23, 2008    Key Record Dates
Last Update Posted: April 8, 2010
Last Verified: January 2008

Keywords provided by University of Edinburgh:
Exercise capacity
PDE5 inhibitors

Additional relevant MeSH terms:
Vascular Diseases
Cardiovascular Diseases
Sildenafil Citrate
Phosphodiesterase 5 Inhibitors
Vasodilator Agents
Phosphodiesterase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Urological Agents
Antihypertensive Agents