Objectives: The aim of this study was to evaluate tear film function in patients with vitamin D deficiency.
Methods: In a single center, 60 eyes of 30 patients with vitamin D deficiency (group 1), and 60 eyes of 30 healthy individuals (group 2) were evaluated using the Ocular Surface Disease Index (OSDI) questionnaire, Schirmer I test, tear break-up time (TBUT), scoring of ocular surface fluorescein staining using a modified Oxford scale, and tear osmolarity.
Results: Tear osmolarity values, OSDI, and Oxford scale scores were significantly higher in group 1 (309±9 mOsm/L, 35.78±21.44 and 1.3±0.9, respectively) compared with group 2 (295±10 mOsm/L, 18.69±17.21 and 0.4±0.8, respectively) (P<0.001 for all). Schirmer I test and TBUT results in group 1 (8.5±3.7 mm and 8.7±0.6 sec, respectively) were significantly lower compared with group 2 (16.6±2.4 and 18.1±0.5, respectively) (P<0.001 for all).
Conclusions: 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.