The Role of Vitamin D in Corneal Epithelial Barrier Function, Ocular Microbiome, Ocular Inflammation, and Visual Acuity of Children With Allergic Conjunctivitis

Allergic Conjunctivitis Clinical Trial

Official title:

The Role of Vitamin D in Corneal Epithelial Barrier Function, Ocular Microbiome, Ocular Inflammation, and Visual Acuity of Children With Allergic Conjunctivitis

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05839938
• Other study ID #: CMUH111-REC1-044
• Status: Recruiting
• Phase: N/A
• Start date: August 8, 2022
• Est. completion date: July 31, 2025

Study information

• Verified date: May 2023
• Source: China Medical University Hospital
• Contact: Chang-Ching Wei
• Phone: 886422052121
• Email: d5522[@]mail.cmuh.org.tw
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

A double-blind study to evaluate the role of vitamin D in corneal epithelial barrier function, ocular microbiome, ocular inflammation, and visual acuity of children with allergic conjunctivitis.

Description:

The prevalence of allergic conjunctivitis (AC) has rapidly increased in recent decades, resulting in a significant global public health concern. The ocular surface is a unique mucosal immune compartment in which immunological features act in concert to foster a tolerant microenvironment (immune privilege). The corneal epithelial barrier is the first line of defense that forms a protective barrier against pathogens, pollutants, and allergens. The ocular microbiota has a role in maintaining the homeostasis of the ocular surface and preservation of barrier function. Vitamin D functions as enforcing intercellular junctions and maintaining intestinal epithelial barrier integrity; metabolites from the gut microbiota may also regulate expression of vitamin D receptor (VDR). Low serum vitamin D levels have been shown to predispose to a variety of allergic disorders. A recent study shows that corneas contain vitamin D and VDR; vitamin D enhances corneal epithelial barrier function. However, research data of the role of vitamin D in ocular microenvironment of AC are insufficient and controversial. In recent research, the investigators found allergic inflammation of ocular surface weakened corneal epithelial barrier, modulated the signal pathway of retinal pigment epithelial cells, and enhanced scleral tissue remodeling, resulting in myopia in progression. However, there are few studies available to investigate the role of vitamin D in ocular surface microenvironment, ocular inflammation, and visual acuity in AC. Moreover, understanding the interaction of vitamin D, ocular microbiota, and ocular inflammation may provide a new target for the development of therapeutic interventions of ocular allergy and restore visual function.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 150
• Est. completion date: July 31, 2025
• Est. primary completion date: July 31, 2025
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 6 Years to 18 Years

Eligibility

Inclusion Criteria:

1. Children aged 6-18 years with allergic conjunctivitis (AC) diagnosed by ophthalmologists or allergists

Exclusion Criteria:

1. Previous eye surgery

2. Active eye infection

3. Any active inflammatory eye disease except AC

4. Systemic steroid use within 28 days of study

Related Conditions & MeSH terms

• Allergic Conjunctivitis
• Conjunctivitis
• Conjunctivitis, Allergic
• Inflammation

Intervention

Other:
• Vitamin D
Vitamin D (2000IU/day) for 6 months
• Placebo
Placebo

Locations

Country	Name	City	State
Taiwan	China Medical University Hospital	Taichung

Sponsors (1)

Lead Sponsor	Collaborator
China Medical University Hospital

Country where clinical trial is conducted

Taiwan, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Levels of vitamin D	Vitamin D will be measured in a blood sample by ELISA to determine baseline status.	Month 0
Primary	Levels of vitamin D	Vitamin D will be measured in a blood sample to follow the change from baseline in vitamin D level at month 6.	Month 6
Primary	Single nucleotide polymorphism of vitamin D receptor and vitamin D binding protein	Single nucleotide polymorphism (SNP) genotyping will be performed in a blood sample by using TaqMan SNP genotyping assays.	Month 0
Primary	Microbiome	Nasal, subconjunctival and anal swabs will be used to detect ocular surface, nasal and intestinal microbiome by using 16S rRNA sequencing to determine baseline status.	Month 0
Primary	Microbiome	Nasal, subconjunctival and anal swabs will be used to detect ocular surface, nasal and intestinal microbiome by using 16S rRNA sequencing, and to follow the change from baseline in microbiome at month 6.	Month 6
Primary	Total IgE	Plasma total IgE concentration will be measured by microparticle immunoassay (IMx analyzer, Abbott Laboratories, Abbott Park, IL) and ELISA to determine baseline status.	Month 0
Primary	Total IgE	Plasma total IgE concentration will be measured by microparticle immunoassay (IMx analyzer, Abbott Laboratories, Abbott Park, IL) and ELISA to follow the change from baseline in total IgE at month 6.	Month 6
Primary	Allergen-specific IgE	Plasma allergen-specific IgE will be measured by BioIC ®.	Month 0
Secondary	mini-Rhinoconjunctivitis Quality of Life Questionnaire (mini-RQLQ)	mini-RQLQ is to measure a the level of severity of a set of symptoms of functional impairments due to rhinoconjunctivitis. 14 questions each range 0-6 (6 is most severe). Total range 0-84 (higher scores reflect lower quality of life.)	Month 0 to Month 6