Elevated tear interleukin-6 and interleukin-8 levels associated with silicone hydrogel and conventional hydrogel contact lens wear

The aim of this study was to evaluate the ocular tear interleukin (IL)-6 and IL-8 concentrations within the first 6 months of contact lens (CL) wear in eyes of neophyte CL users who had been commenced on either silicone hydrogel CL (SH-CL) or conventional hydrogel CL (CH-CL).

Twenty-four subjects with no history of CL wear received either SH-CL (n=12) or CH-CL (n=12) for a period of 6 months in this prospective study. Tear IL-6 and IL-8 concentrations were determined before CL wear (0 months) and at 1, 3, and 6 months after CL commencement. The sera of all the subjects were tested and graded (grades 0-6) for grass, weed, and tree pollen-specific immunoglobulin E (IgE) levels.

Tear IL-6 concentrations at 0, 1, 3, and 6 months for SH-CL and CH-CL users were 7.1 ± 6.4, 10.5 ± 8.9, 18.6 ± 17.0, 33.1 ± 15.0 pg/mL and 10.9 ± 8.2, 6.4 ± 4.0, 24.2 ± 13.2, 34.4 ± 17.5 pg/mL, respectively. In both groups, IL-6 levels were significantly elevated at 6 months compared with those at 0 months (P<0.001). Tear IL-8 concentrations at 0, 1, 3, and 6 months for SH-CL and CH-CL users were 107.4 ± 56.8, 106.0 ± 47.4, 319.5 ± 154.8, 412.6 ± 104.1 pg/mL and 176.4 ± 59.7, 196.2 ± 145.0, 410.7 ± 121.2, 456.7 ± 19.2 pg/mL, respectively. In both groups, tear IL-8 levels were significantly elevated at 6 months compared with those at 0 months (P<0.001). The tear IL-6 and IL-8 levels were found to be similar within the 2 groups at the 6-month time point (P>0.05). The serum grass, weed, and tree pollen-specific IgE levels were similar between groups (P>0.05) and less than 0.35 kU/L (grade 0) in 22 of 24 (91.7%) participants tested.

The SH-CL and CH-CL wear is associated with elevation of IL-6 and IL-8 levels in the tears of healthy, nonatopic neophyte CL users.