Dear Editor,
We would like to thank you for the opportunity to respond to the issues raised in the letter to the editor that was recently directed to us, and to clarify aspects of our methodology in relation to these concerns. We would also like to thank the authors of the letter for their interest in our article studying dry eye and meibomian glands in vitiligo, and for taking their valuable time to express their concerns.
In their letter, the authors recommended cigarette smoking as an exclusion criterion, as there may be a relationship between smoking and dry eye disease (DED) due to its influence on tear film quantity and quality. This association has been described previously in the scientific literature. However, the findings in this case are contradictory, and further investigations and meta-analysis are needed to validate the role of smoking in the incidence of dry eye.1 Moreover, there are similar studies that have not excluded the smokers.2,3
They rightly recommended the exclusion of vitiligo patients using topical medications, especially immunosuppressant agents (i.e., cyclosporine A), in the pre-ocular area because of the beneficial effects of cyclosporine A on DED. In agreement with them, we mentioned “recent use of drugs affecting the lacrimal unit” as an exclusion criterion. It is necessary to explain that topical cyclosporine A is not a conventional medicine in vitiligo treatment4, and none of our patients received this drug.
They also recommended excluding not only current contact lens users but also recent contact lens users. We agree that contact lenses affect the ocular surface and it takes time to recover to normal. None of our patients have ever used contact lenses. Based upon our practice, it is interesting to note that contact lens use is not common in our geographic region due to dusty air.
The authors properly suggested validated Persian questionnaire of Ocular Surface Disease Index (OSDI) instead of an English version. While appreciating the study of Pakdel et al.,5 unfortunately, we did not have access to the Persian version of the OSDI at the time of our study. However, in order to reduce any error, each item of the questionnaire was explained in a language understandable to the patient and then filled in by the researcher (B.H.R) himself. Of note, there are many studies in non-English speaking countries that utilize the original version of the OSDI.6,7 We hope to access and use the Persian version of this questionnaire in future studies on dry eye.