Methodology and enrollment findings of the Beijing adult dry eye cohort study.

BACKGROUND/OBJECTIVES: To describe the design, methodology, and enrollment-stage baseline findings of the Beijing Adult Dry Eye Cohort (ADEC), a population-based cohort established to investigate the epidemiology and longitudinal natural history of dry eye disease (DED) in urban Beijing. METHODS: ADEC is a population-based cohort conducted in Dongcheng District, Beijing. Between 15 July and 31 August 2023, 1,249 adults were randomly selected from 15 communities using stratified cluster sampling; 1,143 completed baseline assessment (response rate 91.5%). Examinations included the Ocular Surface Disease Index (OSDI), non-invasive tear break-up time (NIBUT), tear meniscus height (TMH), meibography, lid margin evaluation, ocular redness analysis, and corneal fluorescein staining, together with demographic, systemic, lifestyle, environmental, and psychological assessments. Prevalence estimates were calculated at the participant level, and generalized estimating equations were used for inferential analyses involving eye-level ocular surface parameters. RESULTS: The baseline analytic sample included 1,091 participants (mean age 54.8 ± 18.0 years; 62.6% female), with eye-level ocular surface measurements available for up to 2,180 eyes depending on the parameter assessed. The crude prevalence of DED, defined as an OSDI score ≥13 together with average NIBUT <10 s in either eye, was 33.7%. After age-sex standardization to the 2020 Chinese Census, the prevalence was 27.0% (95% CI: 23.8-30.3%). The crude prevalence of SDE, aqueous-deficient (AD) phenotype, and MGD phenotype was 34.7, 33.6, and 31.0%, respectively. Mean average NIBUT was 12.0 ± 4.2 s and mean TMH was 0.19 ± 0.07 mm. Participant-level average NIBUT was negatively correlated with anxiety (Spearman r = -0.535, p < 0.001) and depression (Spearman r = -0.425, p < 0.001). Participants with daily electronic device use >2 h comprised 71.0% of the cohort, and 5.1% had autoimmune or rheumatic disease. CONCLUSION: These enrollment-stage ADEC findings characterize the burden and ocular surface profile of dry eye disease among community-dwelling adults in urban Beijing and provide a foundation for subsequent longitudinal analyses within the cohort.