Of the congenital risk factors associated with dry eye disease (DED), Asian ethnicity stands out. Hoping to explore this correlation and the natural history of DED, researchers from New Zealand looked into ethnic population studies that aimed to reduce the potentially confounding effects of methodological and environmental heterogeneity.

Of the 96 total relevant studies the team pooled together, only three possessed sufficient methodological homogeneity for analysis. Two of these studies further indicated susceptibility of the Asian population to iatrogenic DED secondary to contact lens wear and refractive surgery.

From the study findings, the researchers found that the earliest disparities detected between Asian and Caucasian populations were higher degrees of incomplete blinking and lid wiper epitheliopathy in pediatric Asian participants—likely associated with anatomically predisposed increased eyelid tension. They noted that there was an inter-ethnic divergence in meibomian gland dropout in young adults, while other ocular surface characteristics remained within physiological limits. They added that significant differences in meibomian gland function, tear film stability and osmolarity, DED symptomology and overall disease diagnosis did not manifest until adults reached their middle-aged years, and disparities in corneal and conjunctival staining became significant only with older age. The team also discovered that aqueous tear deficiency was less likely than evaporative mechanisms to be implicated in the Asian ethnicity’s propensity toward DED development.

“Overall, the observation of increasing inter-ethnic ocular surface differences throughout life has potential to offer valuable insight into the natural history of dry eye disease development,” the authors concluded in their paper on the study.

Wang MTM, Craig JP. Natural history of dry eye disease: perspectives from inter-ethnic comparison studies. Ocular Surface. April 6, 2019. [Epub ahead of print].