Assessment of the Effect of Vitamin D Deficiency on Ocular Dryness

Background Dry eye syndrome (DES) is one of the most common ocular diseases and has been recognized as an important public health problem. Dry eye is associated with chronic eye pain and an increased risk of ocular surface diseases, such as corneal ulcers and corneal abrasions. DES is a multifactorial disorder of the tear film and ocular surface, Aim and objectives was two-fold: (i) to demonstrate the relation between vitamin D deficiency, dry eye and impaired tear function; (ii) to investigate the possible associations among clinical parameters of hypovitaminosis D, such as fatigue, functional impairment and pain, with dry eye parameters including quantity of tears, the stability of the tear film layer and symptoms of ocular irritation. Subjects and methods Our study was a prospective, non-randomized study which was conducted on 36 patients with Vitamin D deficiency; The 36 vitamin D deficiency patients were classified according to dryness of eye into 2 independent groups:(1) DES group (25 patients) according to Schirmer test without anesthesia with results <10mm and Tear break-up time TBUT <10s, (2) Non-DES group (11 patients) according to Schirmer test without anesthesia with results >10mm and Tear break-up time TBUT >10s.To evaluate the relation between vitamin D deficiency, dry eye and impaired tear function The following tests were done to patients in our study: Careful history taking, full ophthalmological examination, Schirmer test, Tear break-up time and Optical coherence tomography (anterior segment).Follow up for our patients in the study after taking vitamin D supplement for 3 month and all the previous tests were repeated again. Results the results revealed that Comparative study between the 2 groups revealed; highly significant decrease in follow up Schirmer test, tear breakup time and tear-film height in DES group; compared to Non-DES eye group (p < 0.01 respectively). Comparative study between the 2 groups revealed non-significant difference regarding follow up tear-film width and vitamin D level (p > 0.05), Conclusion Our work supports that vitamin D deficiency may lead to dry eye which may carry the risk in development conjunctival squamous metaplasia and loss of goblet cells on the ocular surface, and that vitamin D plays a protective role in the development of dry eye, probably by enhancing tear film parameters and reducing ocular surface inflammation.