Environmental risk factors for dry eye disease

Abstract

Dry eye disease (DED) is one of the most frequently encountered ocular conditions, which is clinically under-recognized mainly due to a poor consensus on its diagnosis. It is considered as a multifactorial disease of the ocular surface, where the homeostasis of the tear film is disrupted. In 2017, the Tear Film Ocular Surface Dry Eye Workshop II proposed a global consensus in the diagnosis of DED. For the present thesis, three different studies were performed, in which the recommended diagnostic criteria was used, to provide a wider insight into DED epidemiology. Prevalence rates and risk factors for DED and DED subtypes were estimated among a single population in the UK. DED subtypes included aqueous deficient (ADDE) and evaporative (EDE) forms of the disease, described by measurements of tear meniscus height (TMH), tear evaporation, tear lipid layer thickness (LLT) and meibomian gland dysfunction (MGD). Moreover, a self-administered DED diagnostic method, assessing DED symptoms and the OptrexTM dry eye blink test, was proposed.Accordingly, this thesis has determined:• A prevalence of 19.0-56.3%, 6.2%, 64.2% and 11.1% for DED, ADDE, EDE, and both ADDE and EDE, respectively.• Age, employment status, medication intake, female sex, the presence of any health conditions/problems, poor sleep quality and prolonged outdoor activity as significant risk factors for DED. The last four factors were the most significant.• Age as a significant risk factor for EDE.• Ocular surface staining as the most commonly observed DED sign.• MGD as the most commonly observed EDE sign.• DED diagnosis by symptoms and tear film stability as the most suitable diagnostic method for the disease.• A diagnostic sensitivity of 100% and specificity of 54% of the proposed DED diagnostic method.