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Effect of Smoking on Retinal Vessel Morphology and Functionality

Effect of Smoking on Retinal Vessel Morphology and Functionality: A Case-Control, Clinical Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07261176
Enrollment
40
Registered
2025-12-03
Start date
2021-04-01
Completion date
2024-12-01
Last updated
2025-12-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Smokers

Keywords

smoke

Brief summary

The study aims at evaluating the effect of smoking activity on anatomy and functionality of retinal blood vessels using optical coherence tomography angiography (OCT-A) and dynamic vessel analysis (DVA). This is a low-risk, single-center, case-control, interventional clinical trial. Forty healthy subjects were enrolled: 20 healthy volunteers with regular daily tobacco activity (approximately 10 cigarettes per day for 5-10 years) and 20 healthy volunteers with no tobacco activity as controls. Each subject underwent comprehensive ophthalmologic examination including OCT-A, DVA, and retinal vessel analysis (RVA) at baseline. Examinations were repeated for the smoking group at 3 and 30 minutes after smoking activity, and for controls at 8 and 35 minutes after baseline to assess examination variability. The primary outcomes assessed changes in retinal perfusion and retinal vascular response after cigarette smoking compared to controls.

Interventions

BEHAVIORALCigarette Smoking

Participants smoked one cigarette containing 0.8 grams of nicotine under standardized conditions. Participants were required to abstain from tobacco activity for 24 hours prior to baseline examination and to avoid vasoconstrictor substances (coffee, alcohol) before examinations.

Sponsors

IRCCS San Raffaele
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE

Intervention model description

Case-control design with two parallel groups: smokers receiving intervention (smoking one cigarette) and non-smoking controls undergoing examinations at matched time intervals.

Eligibility

Sex/Gender
ALL
Age
18 Years to 99 Years
Healthy volunteers
Yes

Inclusion criteria

* Adults of both sexes (age 20 to 30 years old) * Healthy volunteers who can understand and sign informed consent * For Smokers Group: Regular daily tobacco activity (approximately 10 cigarettes per day, smoking duration 5-10 years, using cigarettes with 0.8 grams nicotine content) * For Control Group: No tobacco activity as normal life habit * Willing to abstain from tobacco activity for 24 hours prior to baseline examination * Willing to avoid vasoconstrictor substances (coffee, alcohol) prior to examinations

Exclusion criteria

* Inability to follow planned procedures * Opacity of dioptric media (lens, cornea, or vitreous) that prevents execution of examinations * Known allergies that do not allow pupillary dilation * Ocular pathologies * Systemic hypertension * Diabetes mellitus * Myopia greater than -8.0 Diopters (D) * Hyperopia greater than +5.0 D * Astigmatism greater than -3.0 D

Design outcomes

Primary

MeasureTime frameDescription
Central Retinal Artery Equivalent (CRAE)Baseline, 3 minutes and 30 minutes post-smoking (smokers); baseline, 8 minutes and 35 minutes (controls)Changes in central retinal artery equivalent measured using Retinal Vessel Analyzer (RVA). CRAE relates to the diameter of the central retinal artery, expressed in measurement units (MU). Higher values indicate larger arterial diameter.
Arterial Dilation Percentage Post-Flicker StimulationBaseline, 3 minutes and 30 minutes post-smoking (smokers); baseline, 8 minutes and 35 minutes (controls)Percentage increase in retinal arterial vessel diameter in response to flicker light stimulation measured by Dynamic Vessel Analyzer (DVA). Calculated as percentage increase in vessel diameter relative to baseline after 20 seconds of flicker stimulation, averaged across 3 measurement cycles.

Countries

Italy

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026