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

Purpose

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	Intervention
Ocular Physiology Retina Blood Flow Velocity	Procedure: flicker light stimulation

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Non-Randomized, Open Label, Uncontrolled, Parallel Assignment, Safety/Efficacy Study

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

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Flicker response (Retinal vessel analyzer, Laser Doppler Velocimetry)

Study Start Date:	December 2006
Study Completion Date:	September 2007
Primary Completion Date:	September 2007 (Final data collection date for primary outcome measure)

Eligibility

Ages Eligible for Study:	18 Years to 35 Years
Genders Eligible for Study:	Both
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

Please refer to this study by its ClinicalTrials.gov identifier: 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:	Department of Clinical Pharmacology, Medical University of Vienna ( Gabriele Fuchsjäeger-Mayrl )
Study ID Numbers:	OPHT-121203
First Received:	February 5, 2007
Last Updated:	July 1, 2008
ClinicalTrials.gov Identifier:	NCT00431730
Health Authority:	Austria: Agency for Health and Food Safety

ClinicalTrials.gov processed this record on October 24, 2008

Sponsored by:	Medical University of Vienna
Information provided by:	Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT00431730