Preinflammatory Signs in Established Reusable and Disposable Contact Lens Wearers
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.PURPOSE
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.METHODS
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.RESULTS
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).CONCLUSIONS
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.