Effect of Smoking on Retinal Vessel Morphology and Functionality

NCT07261176 | Completed

• 1 other identifier: SMOKE-DVA
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

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.

Conditions

Smokers

Keywords

smoke

Outcome Measures

Primary Outcomes (2)

• Central Retinal Artery Equivalent (CRAE)

  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

  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)

Study Arms (2)

Smokers Group

EXPERIMENTAL

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

Non-smokers Control Group

NO INTERVENTION

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.

Interventions

Cigarette Smoking BEHAVIORAL

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.

Smokers Group

Eligibility Criteria

• Age: 18 Years - 99 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• IRCCS San Raffaele: lead

Study Sites (1)

Università Vita Salute San Raffaele

Milan, Italy

Location

Related Publications (7)

• Zhu X, Yang K, Xiao Y, Ye C, Zheng J, Su B, Zheng Y, Zhang X, Shi K, Li C, Lu F, Qu J, Li M, Cui L. Association of cigarette smoking with retinal capillary plexus: an optical coherence tomography angiography study. Acta Ophthalmol. 2022 Nov;100(7):e1479-e1488. doi: 10.1111/aos.15157. Epub 2022 Apr 9.

  PMID: 35396902 BACKGROUND

• Garhofer G, Resch H, Sacu S, Weigert G, Schmidl D, Lasta M, Schmetterer L. Effect of regular smoking on flicker induced retinal vasodilatation in healthy subjects. Microvasc Res. 2011 Nov;82(3):351-5. doi: 10.1016/j.mvr.2011.07.001. Epub 2011 Jul 12.

  PMID: 21771603 BACKGROUND

• Ciesielski M, Rakowicz P, Stopa M. Immediate effects of smoking on optic nerve and macular perfusion measured by optical coherence tomography angiography. Sci Rep. 2019 Jul 15;9(1):10161. doi: 10.1038/s41598-019-46746-z.

  PMID: 31308472 BACKGROUND

• Siedlecki J, Mohr N, Luft N, Schworm B, Keidel L, Priglinger SG. Effects of Flavanol-Rich Dark Chocolate on Visual Function and Retinal Perfusion Measured With Optical Coherence Tomography Angiography: A Randomized Clinical Trial. JAMA Ophthalmol. 2019 Dec 1;137(12):1373-1379. doi: 10.1001/jamaophthalmol.2019.3731.

  PMID: 31556937 BACKGROUND

• McClintic SM, Jia Y, Huang D, Bailey ST. Optical coherence tomographic angiography of choroidal neovascularization associated with central serous chorioretinopathy. JAMA Ophthalmol. 2015 Oct;133(10):1212-4. doi: 10.1001/jamaophthalmol.2015.2126. No abstract available.

  PMID: 26135638 BACKGROUND

• Huang Y, Zhang Q, Thorell MR, An L, Durbin MK, Laron M, Sharma U, Gregori G, Rosenfeld PJ, Wang RK. Swept-source OCT angiography of the retinal vasculature using intensity differentiation-based optical microangiography algorithms. Ophthalmic Surg Lasers Imaging Retina. 2014 Sep-Oct;45(5):382-9. doi: 10.3928/23258160-20140909-08.

  PMID: 25230403 BACKGROUND

• de Carlo TE, Romano A, Waheed NK, Duker JS. A review of optical coherence tomography angiography (OCTA). Int J Retina Vitreous. 2015 Apr 15;1:5. doi: 10.1186/s40942-015-0005-8. eCollection 2015.

  PMID: 27847598 BACKGROUND

Related Links

• IRCCS Ospedale San Raffaele Official Website
• Vita-Salute San Raffaele University

Study Officials

• Francesco Bandello, MD

  Ospedale San Raffaele

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

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

Study Record Dates

• First Submitted: November 21, 2025
• First Posted: December 3, 2025
• Study Start: April 1, 2021
• Primary Completion: December 1, 2024
• Study Completion: December 1, 2024
• Last Updated: December 3, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

IT (1)