The effects of tobacco waterpipe smoking on the ocular surface

Background Tobacco smoking has been reported to have many systemic and ocular adverse effects. However, the effect of specific delivery methods of tobacco using a waterpipe on the eye has not been commonly studied. Methods This study enrolled 33 waterpipe smokers (with no history of cigarette smoking) and 31 non-smokers of age-matched control group. Participants were tested in the following sequence: the presence of ocular symptoms using Ocular Surface Disease Index questionnaire, tear osmolarity, tear film break-up time and corneal staining. Statistical analysis using unpaired sample t-tests was performed to study the difference in ocular surface parameters obtained for each group. The prevalence of dry eye disease was also measured in each group. Results The mean tear osmolarity values and corneal staining were significantly higher (P < 0.05) in the waterpipe smoking group (314.64 +/- 15.24 mOsm/L and 0.73 +/- 0.94, respectively) compared to non-smokers (306.42 +/- 13.48 mOsm/L and 0.10 +/- 0.30, respectively). The mean values obtained from tear film break-up time test were significantly lower (P < 0.05) in the waterpipe smoking group (5.82 +/- 3.77 s) compared to non-smokers (8.32 +/- 3.46 s). The difference in the average Ocular Surface Disease Index scores in the study groups was not statistically significant (P > 0.05). The prevalence of dry eye disease was significantly higher (p < 0.05) in the waterpipe smoking group (57.6%), compared to the control group (35.5%). Conclusion Waterpipe smoking could have a significant effect on tear film parameters and be associated with dry eye disease. Dryness also seems to be more prevalent among waterpipe smokers.