If your patients are vitamin D deficient, there’s a good chance they may be more susceptible to dry eye, a new study in Eye & Contact Lens reports.

 In an effort to investigate tear film function in patients with vitamin D deficiency, a team of Turkish researchers evaluated 60 eyes of 30 patients who had vitamin D deficiency and a comparable number of healthy individuals. The doctors evaluated the patients through the Ocular Surface Disease Index (OSDI) questionnaire, Schirmer I test, tear osmolarity, tear break-up time (TBUT) and a scoring of ocular surface fluorescein staining using a modified Oxford scale.  

Researchers noted tear osmolarity, OSDI and Oxford scale scores were significantly higher in the vitamin D deficient group compared with the healthy group. The study also found Schirmer I test and TBUT results in the vitamin deficient group were significantly lower  compared with the healthy eyes.

“This study demonstrates that vitamin D deficiency is associated with tear hyperosmolarity and tear film dysfunction. Patients with vitamin D deficiency may be prone to dry eye,” the investigators wrote in their paper.

Since there is no pathognomonic sign to distinguish dry eye with vitamin D deficiency by slit lamp alone, patients with vitamin D deficiency should be further evaluated if they have syndromes causing dry eye. Equally, dry eye patients should be tested for vitamin D deficiency, the investigators suggested.