Evaluation of the effect of chronic smoking habit on corneal endothelial cells, central corneal thickness and dry eye tests

Aim: The aim of our study was to evaluate the effects of chronic smoking habit on corneal endothelial cells, central corneal thickness,and dry eye tests.Material and Methods: A total of 160 eyes of 160 chronic smokers and 160 eyes of 160 control cases were included in the study. Thesmokers were grouped into 4 groups according to pack-year smoking as follows: 0-10, 10-20, 20-30, >30. Endothelial cell density(CD), average cell size (AVG), percentage of hexagonal cell (HEX), and coefficient of variation (CV), central corneal thickness (CCT)were measured using a specular microscope. The Tear Break-Up Time (TUBT) and Schirmer tests were performed.Results: In Group 1 and Group 2, there was no significant difference between the smoker and the control groups in terms of CD, AVG,HEX and CV. In Group 3 and Group 4, there was a significant decrease in CD and HEX values, while there was a significant increasein AVG and CV values. CCT values were not significantly different in the Groups 1,2 and 3, whereas there was a significant decreasein the Group 4. TBUT and Schirmer tests were significantly decreased in all groups.Conclusion: It was found that as the number of pack-year increased, CD and HEX values decreased and AVG and CV values increased.Dry eye tests were affected in a shorter period of time, while CCT was affected in a longer period of time than the time required forCD, HEX, AVG and CV parameters to be affected.