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Correlation between tear fluid and serum vitamin D levels.
Swaminathan Sethu1, Rohit Shetty2, Kalyani Deshpande2
1GROW Research Laboratory, Narayana Nethralaya Foundation, #258/A Hosur Road, Narayana Health City, Bommasandra, 560099 Bangalore, India.
Eye and Vision (London, England)
|September 6, 2016
Summary
This study found significantly higher vitamin D levels in tears than serum among healthy volunteers. Tear vitamin D may be important for understanding ocular surface diseases.
Area of Science:
- Ophthalmology
- Endocrinology
- Biochemistry
Background:
- Vitamin D deficiency is linked to systemic diseases, including eye disorders.
- Understanding vitamin D's role in ocular health requires further investigation.
Purpose of the Study:
- To measure vitamin D levels in human tears.
- To examine the correlation between serum and tear vitamin D concentrations.
Main Methods:
- Observational cohort study of 48 healthy volunteers.
- Collected serum and tear fluid samples.
- Quantified 25-hydroxyvitamin D using competitive chemiluminescent ELISA.
Main Results:
- Tear 25-hydroxyvitamin D levels were significantly higher (p < 0.0001) than serum levels.
- Tears showed approximately a 2-fold higher concentration of vitamin D compared to serum.
- A positive correlation (r = 0.5595, p < 0.0001) was found between serum and tear vitamin D.
Conclusions:
- Tear fluid contains higher concentrations of 25-hydroxyvitamin D than serum.
- Tear vitamin D levels warrant consideration in research on ocular surface diseases.
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