EC Ophthalmology

Purpose: Tobacco smoking is known to trigger an increase in levels of oxygen radicles in aqueous humor and other ocular tissues, decreased levels of antioxidants such as ascorbic acid. This study aims to compare effects of chewing versus smoking tobacco on corneal endothelial health.

Materials and Methods: This cross-sectional study was conducted at tertiary hospital which included 273 participants divided into three cohorts: 91 tobacco smokers, 91 tobacco chewers, and 91 non-tobacco users. They were evaluated for demographic data, history of systemic comorbidities. Corneal endothelial evaluation done by non-contact specular microscopy. Endothelial cell density, coefficient of variation in cell size, % hexagonality, maximum cell area, minimum cell area and standard deviation of cell area recorded and compared among three groups. Categorical data was represented in the form of frequencies and proportions. Chi-square test or Fischer’s exact test (for 2x2 tables only) was used as test of significance for qualitative data. Continuous data was represented as mean and standard deviation. ANOVA was used as the test of significance to identify the mean difference between three groups. MS Excel and MS word was used to obtain various types of graphs. P value <0.05 was considered as statistically significant after assuming all the rules of statistical tests.

Results: Out of 273 participants, 126 (46.1%) were male and 146 (53.4%) were females. Mean age was 58 ± 2 years in all three groups. ECD and hexagonality was highest among non-tobacco users and least among tobacco chewers. All other endothelial parameters were highest among tobacco chewers compared to tobacco smokers and non-tobacco users.

Conclusion: The effects of tobacco chewing, in addition to smoking on corneal health cannot be underrated. This study points to evidence that chewers may be at a higher risk of corneal endothelial changes as compared with smokers. Therefore, it becomes imperative that these patients must undergo extensive pre-surgical evaluation in terms of a thorough corneal endothelial structural analysis when planning for a vision-improving surgery such as cataract surgery.

 Keywords: Tobacco Chewers; Tobacco Smokers; Endothelial Cell Parameters; Specular Microscopy

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