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

• Sponsor: Medical University of Vienna (Other)
• Overall Status: Completed
• CT.gov ID: NCT00431730
• Collaborator: (none)
• Location: 1
• Duration (Months): 9

Study Details

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	Phase
Ocular Physiology; Retina; Blood Flow Velocity	Procedure: flicker light stimulation	N/A

Study Design

• Study Type: Interventional
• 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: Dec 1, 2006
• Actual Primary Completion Date: Sep 1, 2007
• Actual Study Completion Date: Sep 1, 2007

Outcome Measures

Primary Outcome Measures

1. Flicker response (Retinal vessel analyzer, Laser Doppler Velocimetry) []

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 35 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

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

Locations

	Site	City	State	Country	Postal Code
1	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

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• ClinicalTrials.gov Identifier: NCT00431730
• Other Study ID Numbers: OPHT-121203
• First Posted: Feb 6, 2007
• Last Update Posted: Jul 4, 2008
• Last Verified: Jun 1, 2008

Study Results

No Results Posted as of Jul 4, 2008