Wearing face masks and possibility for dry eye during the COVID-19 pandemic.

This population-based observational, cross-sectional, and descriptive survey was to investigate the relationship of increased face mask usage in the coronavirus disease (COVID-19) era with mask-associated dry eye (MADE). Participants aged 6-79 years old with formal school education were selected. All participants finished the 19-item questionnaire online, distributed through different social media platforms. From 6925 participants who submitted eligible questionnaires, MADE was reported in 547 participants, which included 419 participants who developed new dry eye symptoms after wearing face masks and 128 participants whose pre-existing dry eye symptoms worsened with mask wearing. Longer time of face mask wearing, nonstandard wearing of face masks, reduced outdoor time, decreased daily reading time, shortened visual display terminals time, and dry environment were positively associated with MADE. There were significant associations between perceived MADE and age, female sex, education, use of glasses and contact lenses, and pre-existing dry eye. MADE was more common in adults aged > 20 years than those aged ≤ 20 years or juveniles. MADE incidence increased. Standard wearing of face masks was suggested as a protective factor for MADE. Awareness about the possible risk of MADE should also be created and the clinical dry eye signs should be verified.Clinical trial registration number: NCT04744805.