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Is There a Difference in Flicker Induced Vasodilatation Between Smokers and Non-Smokers?

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ClinicalTrials.gov Identifier: NCT00431730
Recruitment Status : Completed
First Posted : February 6, 2007
Last Update Posted : July 4, 2008
Sponsor:
Information provided by:

Study Description
Brief Summary:

Habitual smoking is associated with an increased risk of coronary artery disease, cerebral and peripheral vascular disease, including ocular diseases like age-related macular degeneration or diabetic retinopathy. Data of a recent study performed in the investigators lab revealed abnormal choroidal blood flow regulation in chronic smokers as compared to age-matched non-smoking subjects during isometric exercise. However, no information is yet available about the regulation of retinal vascular tone in habitual smokers.

Thus, in the current study, the investigators set out to investigate whether the regulation of retinal vessels diameters is affected in habitual smokers. It has been shown in several reports that stimulation with diffuse luminance flicker, increases retinal arterial and venous diameters, indicating for the ability of the retina to adapt to changing metabolic demands. In the current study we use this effect as a tool to investigate whether the flicker induced vasodilatation is affected in habitual smokers. This would indicate for an impaired vascular regulation process in smokers.


Condition or disease Intervention/treatment
Ocular Physiology Retina Blood Flow Velocity Procedure: flicker light stimulation

Study Design

Study Type : Interventional  (Clinical Trial)
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Official Title: Is There a Difference in Flicker Induced Vasodilatation Between Smokers and Non-Smokers?
Study Start Date : December 2006
Primary Completion Date : September 2007
Study Completion Date : September 2007
Arms and Interventions


Outcome Measures

Primary Outcome Measures :
  1. Flicker response (Retinal vessel analyzer, Laser Doppler Velocimetry)

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 35 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • 24 subjects aged between 18 and 35 years, nonsmokers (since at least 2 years)
  • 24 subjects aged between 18 and 35 years, smokers (at least 10 cigarettes/day since 2 years)
  • Body mass index between 15th and 85th percentile
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant
  • Normal ophthalmic findings, ametropy < 3 dpt.

Exclusion Criteria:

  • Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
  • Treatment in the previous 3 weeks with any drug
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with distribution, metabolism or excretion of study drugs
  • Blood donation during the previous 3 weeks
  • Ametropy >= 3 dpt
Contacts and Locations

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 ClinicalTrials.gov identifier (NCT number): NCT00431730


Locations
Austria
Department of Clinical Pharmacology
Vienna, Austria, 1090
Sponsors and Collaborators
Medical University of Vienna
Investigators
Principal Investigator: Gabriele Fuchsjaeger-Mayrl, MD Department of CLinical Pharmacology, Medical University of Vienna
More Information

Responsible Party: Gabriele Fuchsjäeger-Mayrl, Department of Clinical Pharmacology, Medical University of Vienna
ClinicalTrials.gov Identifier: NCT00431730     History of Changes
Other Study ID Numbers: OPHT-121203
First Posted: February 6, 2007    Key Record Dates
Last Update Posted: July 4, 2008
Last Verified: June 2008