Indoor Airborne Microbial Concentration and Dry Eye.

Area of Science:

• Ophthalmology
• Environmental Health
• Microbiology

Background:

• Dry eye (DE) is a prevalent ocular surface condition.
• Indoor airborne microbial concentrations are increasingly recognized as potential environmental health factors.
• The relationship between indoor microbial exposure and specific DE measures requires further investigation.

Purpose of the Study:

• To investigate the association between indoor airborne microbial concentrations and clinical measures of dry eye.
• To identify specific DE signs that correlate with microbial colony-forming units (CFU) in the home environment.

Main Methods:

• A prospective, observational, cross-sectional study involving 157 participants with normal ocular anatomy.
• Indoor air sampling using bioaerosol impactors to quantify microbial colony-forming units (CFU).
• Clinical assessment of DE symptoms and signs, including corneal epithelial disruption and meibomian gland (MG) dropout.

Main Results:

• Higher CFU counts were observed in older homes compared to newer homes.
• A 1% increase in humidity correlated with a 3% increase in nutrient CFU.
• Instrumented CFU significantly associated with corneal epithelial disruption and lower eyelid MG dropout.
• CFU and age remained significant predictors of MG dropout after adjusting for confounders.

Conclusions:

• Elevated indoor airborne microbial concentrations (CFU) in the home are associated with more severe meibomian gland dropout.
• Home microbial exposure may be a modifiable factor impacting meibomian gland dysfunction, a component of dry eye disease.
• Targeting indoor microbial exposure could represent a novel intervention strategy for managing dry eye.