Acute Ocular Effects of Cigarette Smoking

Istanbul University90 enrolled

Overview

This prospective study aims to evaluate the short-term effects of smoking on corneal tomographic and biometric measurements in healthy adults. After baseline examinations and measurements are taken in both smoking and non-smoking participants, the same measurements will be repeated after 10 minutes of external exposure, and within-group and between-group changes will be compared. The aim of the study is to determine whether acute smoking exposure leads to measurable immediate changes in corneal tomographic and biometric parameters.

This study is a single-center, prospective, and controlled study designed to evaluate the short-term effects of smoking on corneal tomographic and biometric measurements in healthy adults. The study aimed to include 46 smokers and 46 non-smokers. To avoid inter-eye correlation, only the right eye of each participant was evaluated. All participants initially underwent a full ophthalmological examination and measurements were taken using a Pentacam device. Afterward, all participants waited in standard outdoor conditions for 10 minutes. During this time, participants in the smoking group smoked, while participants in the control group did not smoke. The same measurements were repeated at the end of the period. The study aimed to compare within-group and between-group differences in changes.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Smoking ( Cigarette)Cornea Anterior Eye Segment Measurements

Cigarette Smoking ExposureOTHER

Participants in the smoking group smoked cigarettes during a standardized 10-minute outdoor period between baseline and post-exposure assessments.

No Smoking ExposureOTHER

Participants in the control group remained in the same outdoor environment for 10 minutes without smoking between baseline and post-exposure assessments.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 60 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Healthy adults aged 18 to 60 years * Current smokers in the smoking group * Never-smokers in the control group * Willing and able to undergo ophthalmic examination and Pentacam AXL measurements Exclusion Criteria: * History of ocular surgery or ocular trauma * Presence of corneal disease, retinal disease, or ocular surface disorder * Clinically significant dry eye disease * Contact lens use within the last 2 weeks * Use of medications that may affect the ocular surface or pupillary dynamics, including anticholinergics or sympathomimetics * Systemic diseases such as diabetes mellitus or hypertension * Former smoking history in the control group * Use of electronic cigarettes or other tobacco products * Inability to cooperate adequately for accurate measurement

Outcomes

Primary Outcomes

Change in Pentacam-measured corneal pachymetry at the pupil center after acute cigarette smoking exposure

Change (post-exposure minus baseline) in corneal pachymetry at the pupil center, measured in micrometers (µm) using Pentacam. The magnitude of change will be compared between smokers and non-smokers.

Time frame: Baseline and immediately after a standardized 10-minute outdoor exposure period

Secondary Outcomes

Change in Pentacam-measured corneal densitometry in the anterior 0-2 mm zone after acute cigarette smoking exposure

Change (post-exposure minus baseline) in corneal densitometry in the anterior 0-2 mm zone, measured in grayscale units (GSU) using Pentacam. The magnitude of change will be compared between smokers and non-smokers.