THE EFFECT OF VITAMIN D3 SUPPLEMENTATION IN CONTROL OF DRY EYE IN INDOOR & OUTDOOR ENVIRONMENT

Abstract

Background

Dry eye syndrome (DES) is a multifactorial disorder characterized by tear film instability, ocular surface inflammation, and discomfort, often exacerbated by both intrinsic and extrinsic factors. Vitamin D has been recognized for its anti-inflammatory and immunomodulatory properties, with recent studies suggesting a potential link between vitamin D deficiency and DES. However, the impact of vitamin D supplementation on DES parameters remains unclear. This study aimed to evaluate the association between serum 25-hydroxyvitamin D [25(OH)D] levels and DES incidence and to assess the effect of vitamin D3 supplementation on tear film stability and ocular surface health.

Objective

To determine the relationship between serum 25(OH)D levels and DES parameters and to evaluate the therapeutic impact of vitamin D supplementation on tear stability, inflammation, and symptom severity in individuals from indoor and outdoor environments.

Methods

A randomized controlled trial was conducted on 84 individuals diagnosed with DES, including 44 from an indoor environment and 40 from an outdoor environment. Serum 25(OH)D levels were assessed, and DES parameters, including tear film breakup time (TBUT), fluorescein staining score (FSS), eyelid margin hyperemia, conjunctivochalasis (CCH), Schirmer tear secretion test, ocular surface disease index (OSDI) scores, visual analogue scale (VAS) scores, symptom severity, and duration, were evaluated. Participants with vitamin D deficiency received oral supplementation (60,000 IU/week for eight weeks), and follow-up assessments were performed at 2, 4, 6, and 10 weeks.

Results

Serum 25(OH)D levels were significantly lower in DES patients compared to controls, with a mean value of 10.52 ± 4.61 ng/mL. TBUT values improved significantly from 3.910 ± 0.054 to 4.238 ± 0.022 seconds in the indoor group and from 3.680 ± 0.026 to 4.403 ± 0.118 seconds in the outdoor group at the tenth week (p<0.05). FSS decreased from 0.880 ± 0.042 to 0.183 ± 0.022 in the indoor group and from 0.685 ± 0.045 to 0.166 ± 0.224 in the outdoor group (p<0.05). Hyperemia of the eyelid margin reduced significantly, from 2.582 ± 0.050 to 1.156 ± 0.022 in the indoor group and from 2.270 ± 0.025 to 1.560 ± 0.326 in the outdoor group (p<0.05). Schirmer test values increased from 7.053 ± 0.037 mm to 5.821 ± 0.022 mm in the indoor group and from 6.934 ± 0.055 mm to 7.847 ± 0.681 mm in the outdoor group (p<0.05). OSDI scores significantly improved from 58.977 ± 4.240 to 10.298 ± 0.028 in the indoor group and from 53.892 ± 4.001 to 0.152 ± 0.165 in the outdoor group (p<0.05).

Conclusion

A significant association was observed between serum 25(OH)D levels and DES severity. Vitamin D deficiency was linked to reduced TBUT, tear secretion, and increased ocular surface inflammation. Vitamin D supplementation improved tear film stability, enhanced tear secretion, and alleviated symptoms, suggesting its potential role in DES management. The immunomodulatory effects of vitamin D may influence DES pathogenesis, warranting further research to establish optimal supplementation protocols.