Established reusable contact lens (CL) wearers show higher tear inflammatory cytokine concentrations and greater conjunctival metaplasia in the region covered by standard soft CLs. The balance of proinflammatory to anti-inflammatory cytokines, but not individual tear cytokine concentrations, was associated with self-reported CL discomfort.
Daily disposable (DD) lenses are often used to improve CL discomfort, but the effect on ocular inflammatory responses has not been fully investigated. This study aimed to compare the concentrations of tear cytokines and conjunctival cell morphology in healthy habitual DD and reusable soft CL wearers.
Thirty-six established daily CL wearers, including 14 DD and 24 reusable wearers, were enrolled. Symptoms and ocular surface integrity were evaluated. The concentration of tear cytokines (interleukin 1β [IL-1β], IL-6, IL-10, IL-12(p70), IL-17A, and tumor necrosis factor α) were determined using Multiplex assays. The ratios of proinflammatory and anti-inflammatory cytokines were calculated. Impression cytology was performed on the conjunctiva, and goblet cell density and epithelial squamous metaplasia were quantified. Differences in variables by CL replacement schedules and the associations between variables were analyzed.
Reusable CL wearers had higher concentrations (in pg/mL) of IL-1β (26 ± 7 vs. 16 ± 11), IL-6 (42 ± 14 vs. 25 ± 20), IL-10 (83 ± 23 vs. 49 ± 36), IL-12(p70) (145 ± 44 vs. 91 ± 68), IL-17A (93 ± 26 vs. 54 ± 44), and tumor necrosis factor α (312 [171 to 468] vs. 189 [6 to 447]) (all P < .01) and greater conjunctival metaplasia in the region covered by CLs (0.7 [0.2 to 1.6] vs. 0.4 [0.04 to 1.2], P = .01) compared with DD wearers. There was a positive association between CL discomfort and ratios of IL-1β to IL-10 and IL-12(p70) to IL-10 (ρ = 0.42 and ρ = 0.33, P < .05).
Higher ocular inflammatory responses, as indicated by higher tear cytokine concentrations and higher conjunctival epithelial metaplasia, were found in reusable CL wearers than in DD CL wearers. The balance of proinflammatory and anti-inflammatory cytokines may be helpful to assess the inflammatory status of the eye.
1College of Optometry, State University of New York, New York, New York
2School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia *firstname.lastname@example.org
Submitted: April 7, 2017
Accepted: July 7, 2017
Funding/Support: This study was funded in part by the Schnurmacher Institute for Vision Research at the SUNY College of Optometry. The authors have no proprietary or commercial interests in any concept or product discussed in this article.
Conflict of Interest Disclosure: None of the authors have reported a conflict of interest.
Author Contributions and Acknowledgments: Conceptualization, Methodology, and Writing – Review & Editing: CC, FS, MW, BG, KR; Data Curation, Formal Analysis, Investigation, Project Administration, and Validation: CC; Funding Acquisition and Writing – Original Draft: CC, KR; Supervision: FS, MW, BG, KR; Resources: MW, KR.
The authors acknowledge equipment support from Bio-Rad Laboratories and Dr. Stewart Bloomfield. Part of the results of this study has been reported as an abstract at the American Academy of Optometry meeting in Anaheim, California, 2016.