Tear Inflammatory Cytokines Analysis and Clinical Correlations in Diabetes and Nondiabetes With Dry Eye.

PURPOSE: To enhance the understanding of dry eye (DE) in diabetes by evaluating the ocular surface characteristics and the levels of tear inflammatory cytokines.

DESIGN: Cross-sectional study.

METHODS: Subjects were divided into 4 groups: 32 patients in the diabetes with DE group; 24 patients in the diabetes without DE group; 28 patients in the nondiabetes with DE group; and 29 volunteers in the normal group. Ocular surface disease index (OSDI) was self-answered and ocular surface characteristics including tear film break-up time (BUT), Schirmer I test, corneal fluorescein staining (CFS), and corneal sensitivity were evaluated. Concentrations of epidermal growth factor (EGF), IL-17A, IL-1β, and tumor necrosis factor alpha (TNF-α) were measured by mutiplex bead analysis. Spearman correlations between cytokines and ocular surface parameters were calculated.

RESULTS: The level of EGF in tears significantly increased in the diabetes with DE group and positively correlated with the CFS and negatively correlated with the Schirmer I test in this group (P < .05). No differences were found in the levels of IL-17A, IL-1β, and TNF-α in the diabetes with DE and diabetes without DE groups compared to the normal group (P > .05). The nondiabetes with DE group showed increased levels of IL-17A, IL-1β, and TNF-α in tears compared to the normal group and the levels of IL-1β and TNF-α in tears positively correlated with CFS (P < .05).

CONCLUSIONS: Our study showed that levels of EGF in tears have potential to be the diagnostic biomarker of DE in diabetes. No differences of IL-17A, IL-1β, and TNF-α in tears were found between the diabetes with DE and normal group, suggesting different pathogenesis of diabetes DE vs nondiabetes DE.