Effects of wearing a daily disposable lens on tear film: a randomised controlled trial

Abstract

Purpose

Contact lens‐induced dry eye is commonly encountered, although its extent is not well documented with daily disposable lenses. A novel type of contact lens system incorporating moisturising agent (alginic acid) has been developed. The aim of this study was to evaluate the effect of wearing daily 2‐hydroxyethyl methacrylate disposable contact lenses for seven days on tear stability, conjunctival and limbal redness and dry eye symptoms. Then, we aimed to determine whether lens solutions containing alginic acid had any influence on tear parameters.

Methods

This was a seven‐day parallel group double‐masked clinical trial of previous contact lens wearers, where participants were randomly assigned to wearing SEED 1dayPure moisture contact lenses with (n = 15) or without alginic acid (n = 15). Tear lipid layer thickness (LLT), non‐invasive tear break‐up time (NIBUT), conjunctival redness, corneal fluorescein staining, tear break‐up time and Schirmer I readings were measured. Symptom severity and frequency were evaluated and combined using a global score from visual analogue scales.

Results

The mean age and standard deviation of the participants was 25 ± 3.8 years. There were 24 females and six males. After reintroduction of contact lens wear for one week, there was significant improvement in the global symptom score; however, this may not be clinically significant. There were small and clinically insignificant changes in limbal and conjunctival hyperaemia but no significant changes in lipid layer thickness, Schirmer I and NIBUT in overall participants. The use of alginic acid in lens solutions did not affect these parameters compared to control lenses (p > 0.05).

Conclusions

After seven days of wearing a modern daily disposable lens, there was no significant deterioration of tear function in a group of young contact lens wearers. In this short‐term study, there was no evidence of significant benefit of lens solutions containing alginic acid used with HEMA lenses.

Key words:

• alginic acid
• clinical study
• contact lens
• dry eye
• human
• prospective study
• randomised control trial
• tears

Acknowledgements

We would like to thank SEED Co. Ltd, Japan, for contributing the lenses used in this study.

This research was supported by grants NMRC/CSA/045/2012 from the National Medical Research Council, Singapore and BMRC 10/1/35/19/670 from the Biomedical Research Council, Singapore

Additional information

Funding

National Medical Research Council, Singapore

Biomedical Research Council, Singapore