Abstract
This study is to identify subgroups of DED patients with different tear cytokine profiles and compare their DED symptoms and signs among subgroups. Baseline tear cytokines (IL-1β, IL-6, IL-8, IL-10, IL-17A, IFN-γ and TNF-α) were measured using a magnetic bead assay. DED symptoms were assessed by Ocular Surface Disease Index (OSDI) and signs were assessed by corneal and conjunctival staining, tear break-up time (TBUT), Schirmer's test, tear osmolarity and meibomian gland dysfunction (MGD). Latent profile analysis was performed to identify subgroups, and their scores of DED symptoms and signs were compared using generalized linear regression. Among 131 patients with total tear volume > 4 µl from both eyes, subgroup 1 (n = 23) significantly higher in IL-6 and IL-8 (all p < 0.001) and subgroup 2 (n = 108) significantly higher in IL-10 (p = 0.03), IL-17A (p < 0.001), and IFN-γ (p < 0.001). Both subgroups were similar in demographics and DED symptoms, but subgroup 1 had significantly more severe DED signs: higher conjunctival staining (3.38 vs. 2.69, p = 0.04), corneal staining (4.26 vs. 3.03, p = 0.03), lower Schirmer's test score (8.20 vs. 13.72, p < 0.001), and higher composite severity score of DED sign (0.62 vs. 0.45, p = 0.002). We identified two DED subgroups with different profiles of tear cytokines. Patients in these subgroups differed significantly in DED signs, supporting the inflammation's role in DED development and progression.