Time to get more of the Sunshine Vitamin???
Dry eye disease (DED) is a common and often frustrating condition affecting millions of people worldwide. While artificial tears and warm compresses provide relief for many, researchers continue to explore new treatment approaches. A recent systematic review and meta-analysis, published in Contact Lens & Anterior Eye, suggests that Vitamin D (VD) supplementation may offer benefits for individuals suffering from dry eye.
Vitamin D and Eye Health: The Background
Vitamin D is well-known for its role in bone health, but it also possesses anti-inflammatory and immunomodulatory properties that may influence ocular surface health. Previous studies have identified a link between Vitamin D deficiency (VDD) and dry eye, with lower serum Vitamin D levels correlating with increased DED symptoms. Patients with VDD may be particularly prone to dry eye due to impaired tear production and inflammation.
About the Study
To further explore the effects of Vitamin D supplementation on DED, researchers conducted a systematic review and meta-analysis. They collected studies from 10 databases and four clinical trial registry websites, focusing on research published between 2015 and January 2023. The goal was to assess the impact of VD supplementation on both the signs and symptoms of DED.
What Did the Study Find?
A total of eight studies, including 439 cases, met the inclusion criteria. Reviewers then analysed the data to determine the effect of VD supplementation on various clinical measures of dry eye. These included:
Schirmer’s test (SH test): Evaluates tear production
Tear film break-up time (TBUT): Assesses tear film stability
Corneal fluorescein staining scores (CFSS, Oxford Scale 0-5): Measures corneal damage
Lid hyperemia: Indicates inflammation of the eyelids
Ocular Surface Disease Index (OSDI): Evaluates symptom severity
Visual analog pain scale (VAS): Assesses subjective pain symptoms
The statistical analyses revealed that VD supplementation significantly improved:
Tear production (SMD 1.43, 95% confidence interval [CI] 0.81-2.05, p=0.000)
Tear film stability (SMD 1.19, 95% CI 0.83-1.55, p=0.000)
Additionally, Vitamin D supplementation was found to reduce:
Lid hyperemia (SMD -0.71, 95% CI -1.09 to -0.32, p=0.000)
OSDI scores (symptom severity) (SMD -1.10, 95% CI -1.45 to -0.74, p=0.000)
Pain symptoms (VAS score) (SMD -0.32, 95% CI -0.47 to -0.18, p=0.600)
How Should Vitamin D Be Taken?
Interestingly, the study’s subgroup analysis suggested that oral Vitamin D supplementation had the most significant impact on DED signs and symptoms compared to buccal spray or intramuscular injection. Doses in the included studies ranged from 2,000 IU daily (via spray or capsule) to 200,000 IU in a single intramuscular injection.
Key Takeaways
These findings suggest that Vitamin D supplementation may serve as an effective adjunct therapy for individuals with dry eye disease. Improvements were noted in key DED parameters, including tear production, tear film stability, lid hyperemia, and symptom severity. Oral supplementation, in particular, appeared to provide the greatest benefit.
While further research is needed to refine dosage recommendations and long-term effects, these results highlight an exciting potential role for Vitamin D in managing dry eye symptoms. If you suffer from dry eye, it may be worth discussing Vitamin D levels and supplementation with your healthcare provider and getting your Vitamin D levels checked.
Reference: The efficacy of vitamin D supplementation in dry eye disease: A systematic review and meta-analysis in Cont Lens Anterior Eye 2024 Vol. 47 Issue 5.