Increased corneal epithelial permeability after overnight sleep.

ABSTRACT

PURPOSE: To investigate factors of ethnicity, sex, age, and diurnal variation on human corneal epithelial permeability. METHODS: Data of corneal epithelial permeability to sodium fluorescein (Pdc) were collected from 374 noncontact lens wearers at various times after awakening throughout the day. Mixed-effect models were developed to investigate the association between Pdc and factors of interest, including time awake (TA), age, sex, ethnicity, and interactions of these factors. RESULTS: Two models evaluated the "Pdc recovery period" from awakening to 2 hours (Model 1) and the "Pdc plateau" period after TA of 2 hours (Model 2). In Model 1, Pdc declined significantly with length of awake time (P = 0.000), and showed higher Pdc with males (P = 0.098), although this sex difference was not observed after 2 hours (Model 2). Both models showed significantly higher Pdc in Asians than in non-Asians (P = 0.000) and increased Pdc with age (P = 0.048, P = 0.001). CONCLUSIONS: Baseline corneal epithelial barrier function increases after overnight sleep and varies significantly by ethnicity and age.