Daily disposables are often touted as the healthiest lens alternative, and a new Turkish study backs up this claim, specifically citing this modality as being less damaging to the ocular surface.

In an effort to evaluate how different contact lens replacement schedules and materials impact the ocular surface and tear function, investigators placed participants in three groups: group one consisted of 22 subjects who wore daily disposable hydrogels; group two, with 25 patients who wore daily disposable silicone hydrogels; and the third group of 24 individuals wore reusable silicone hydrogel lenses. Researchers conducted tear functions tests and measured inflammatory cytokine—interleukin (IL)-6, IL-8, IL-17A and matrix metalloproteinase (MMP)-9—levels prior to wear and then again after one and three months following lens wear. Additionally, the study evaluated impression cytology before the patients put on the lenses and then again after three months. 

Researchers reported a statistically significant difference between the groups in the levels of IL-6, IL-8, and IL-17A found in tears at both the first and third months of lens wear, with the lowest levels found in the daily disposable hydrogel group and the highest levels in the group who wore reusable silicone hydrogels. Investigators also noted a statistically significant decrease over time in the Schirmer test in group one, in only the tear break-up time in group two and in the tear break-up time and Schirmer test in group three. Additionally, researchers found a statistically significant increase over time in the levels of IL-6, IL-8, IL-17A and MMP-9 in all groups. In the third month, a significant progression was observed in the Nelson grade in all groups.

“The wear of daily disposable CLs can be considered to cause less damage to the ocular surface and less increase in proinflammatory cytokine levels,” the researchers said in their paper.

Muhafiz E, Bayhan HA, Sahin S, et al. Evaluation of the ocular surface in different contact lens replacement schedules. Cornea. January 24, 2019. [Epub ahead of print].