The Effect of Smoking on Corneal Endothelial Cells

Purpose: To investigate the effect of chronic cigarette smoking on the endothelial cells of the cornea via non contact specular microscopy. Method: In this prospective, cross-sectional study, 25 eyes of 25 chronic smokers and 21 eyes of 21 age-matched, healthy non-smokers were enrolled. The Fagerstrom Test for Nicotine Dependence on Cigarettes was used to determine the nicotine dependency level. The level of cotinine, a major metabolite of nicotine, was measured in urine samples from the control group to detect whether they were passively affected by cigarette smoke. All participants underwent measurement of tear break-up time (TBUT), central corneal thickness (CCT), and axial length. Endothelial cell density and endothelial cell morphology were evaluated by non-contact specular microscopy. Results: On average, the cigarette smokers consumed 19.2 +/- 8.3 cigarettes per day and had been smoking for 14.5 +/- 6.8 years. The mean TBUT value was significantly lower in the smoker group compared to the non-smoker group (p<0.05). No statistically significant difference was found in the mean CCT, mean endothelial cell density, or parameters of endothelial cell morphology between smokers and non-smokers. Conclusion: This study showed that cigarette smoking seems to affect the TBUT value but no effects were found on the parameters of corneal endothelial cells.