Choroidal and retinal nerve fiber layer thicknesses in smokers

Background Tobacco smoking is known for its deleterious effects on the systems of the whole body. However, the effects on the eye are not fully understood, especially the effects on the retina and choroid. Aim The current study aimed to evaluate the effects of smoking on choroidal and retinal nerve fiber layer (RNFL) thicknesses. Patients and methods The current work included 50 patients, categorized into G1 (25 healthy individuals as a control group) and G2 (25 smokers, who practiced continuous smoking for >2 years). All participants were assessed by history taking, followed by ocular examination of both eyes. The unaided and best-corrected visual acuity and intraocular pressure were determined. The slit-lamp biomicroscopic examination was performed to detect any abnormalities or media opacity of the anterior segment of the eye. It was followed by the fundus examination and optical coherence tomography to determine choroidal thickness (CT) and RNFL thickness. Results No significant differences were reported between smokers and nonsmokers regarding patient age, hemoglobin concentrations, visual acuity, or intraocular pressure. The smoking duration ranged between 3 and 30 years, and the number of daily cigarettes ranged between 5 and 30 cigarettes/day. The choroidal thickness and RNFL thickness were significantly reduced among smokers compared with nonsmokers. Finally, there was a significant, inverse correlation between CT and the smoking duration and daily smoking. Conclusion There was a significant reduction in CT and RNFL thicknesses owing to smoking. This reduction could be associated with reduced blood flow to the choroid following smoking.