Effect of Smoking on Retinal Vessel Morphology and Functionality

November 21, 2025 updated by: Querques Giuseppe, IRCCS San Raffaele

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

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

40

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Italy
      • Milan, Italy
        • Università Vita Salute San Raffaele

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Smokers Group
Twenty healthy volunteers with regular daily tobacco activity (approximately 10 cigarettes per day, smoking duration 5-10 years, using cigarettes with 0.8 grams nicotine content). Participants underwent OCT-A, DVA, and RVA examinations at baseline, 3 minutes, and 30 minutes after smoking one cigarette.
Behavioral: Cigarette 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.
No Intervention: Non-smokers Control Group
Twenty healthy volunteers with no tobacco activity as normal life habit. Control participants underwent the same OCT-A, DVA, and RVA examinations at baseline, 8 minutes, and 35 minutes (corresponding timepoints without smoking) to assess examination variability and learning effects.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Central Retinal Artery Equivalent (CRAE)
Time Frame: 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.
Baseline, 3 minutes and 30 minutes post-smoking (smokers); baseline, 8 minutes and 35 minutes (controls)
Arterial Dilation Percentage Post-Flicker Stimulation
Time Frame: Baseline, 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.
Baseline, 3 minutes and 30 minutes post-smoking (smokers); baseline, 8 minutes and 35 minutes (controls)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

IRCCS San Raffaele

Investigators

  • Principal Investigator: Francesco Bandello, MD, Ospedale San Raffaele

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 1, 2021

Primary Completion (Actual)

December 1, 2024

Study Completion (Actual)

December 1, 2024

Study Registration Dates

First Submitted

November 21, 2025

First Submitted That Met QC Criteria

November 21, 2025

First Posted (Estimated)

December 3, 2025

Study Record Updates

Last Update Posted (Estimated)

December 3, 2025

Last Update Submitted That Met QC Criteria

November 21, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • SMOKE-DVA

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Smokers

Clinical Trials on Cigarette Smoking

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Vietnam

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe