Objective: To investigate the effect of e-cigarettes on the tear film by evaluating the tear film parameters of smokers compared to smokers among Qassim University students and workers.
Methodology: A total of 60 males participants of the age group 20-38 years old divided into three groups were recruited to this cross-sectional single-visit study. All subjects underwent four different tests parameters through the Keratograph 5M JENVIS, the tests included are tear meniscus height TMH, nun-invasive tear break-up time NITBUT, ocular redness OR and lipid layer thickness LLT. Ocular redness OR degree was evaluated qualitatively on a scale of 1-4, as 1 being normal, 2 as mild, 3 as moderate and 4 as severe redness. Subjects were asked to open their eyes widely and an image of the eye was captured for the evaluation. Data were analyzed using Statistical Package for Social Sciences (SPSS) with p value of less than 0.05 was considered as significant. Also, One-Way ANOVA has been used which compares the means of the three groups in the study to determine whether there is statistical evidence that the associated population means are significantly different, and T-test was used as a post hoc analysis if there is a difference between the groups.
Results: For this study total of 40 smokers were recruited with mean age of 32.55 ± 9.25. For comparison, 20 nonsmokers were selected with a mean age of 33.85 ± 11.35. Comparing the ocular surface disease index score we observed high mean scores among smokers and vapors (10.85 ± 5.96 and 10.3 ± 7.67 respectively) than nonsmokers (4.25 ± 4.48) with a significant mean difference of 0.001. Tear meniscus height between the three groups was similar without any statistically significant difference (p-value 0.213). Our observations revealed that smoking affects the tear volume by decreasing the mean volume from 6.3 ± 1.41 to 3.2 ± 2.16. We reported a significant difference among the three groups when comparing tear volume through the strip meniscometry tube (SMTube) test (p=0.00001).
Conclusion: A strong positive alarming association has been found between tear breakup time and eye dryness. To understand the impact of e-cigarettes on the eyes more thoroughly, cellular and molecular research into the health of the ocular surface is necessary.