Effect of Vitamin D Deficiency and Its Supplementation on Both Conjunctival Impression Cytology and Tear-Film Changes

Background: Deficiency of vitamin-D led to dry eye disease and its supplementations improves this condition.Aim of the work: This study aims to assess conjunctival impression cytology [CIC] and tear-film parameters in patients of vitamin-D deficiency [VDD], as well as how vitamin-D supplementation affects them.Patients and Methods: This prospective study included 20 participants [40 eyes] with serum vitamin D levels below normal, 20 control subjects [40 eyes] with normal serum vitamin D levels, and 20 participants [40 eyes] after treatment with supplementation of vitamin D. A thorough ophthalmological examination, tear break-up time [TBUT], Schirmer II test, and CIC tests were performed on each subject.Results: Regarding mean serum vitamin D levels [p< 0.001], TBUT scores [p< 0.001], and Schirmer II values [p< 0.001], there was a statistically significant difference among the groups. 65% of patients in the deficient group showed grades 2 or 3 impression cytology, compared to 30% in the control group and 25% in the post-treatment group, according to the Nelson staging system [p< 0.001].Conclusion: Our findings show that VDD causes dry eye, resulting in decreased tear film parameters, conjunctival squamous metaplasia, and loss of goblet cell, whereas vitamin D supplementation improves parameters of the tear film and impression cytology.