Associations between Subjective Happiness and Dry Eye Disease: A New Perspective from the Osaka Study

Importance: Dry eye disease has become an important health problem. A lack of concordance between self-reported symptoms and the outcome of dry eye examinations has raised questions about dry eye disease. Objective: To explore the association between subjective happiness and objective and subjective symptoms of dry eye disease. Design: The study adopted a cross-sectional design. Setting: All the employees of a company in Osaka, Japan. Participants: 672 Japanese office workers using Visual Display Terminals (age range: 26–64 years). Methods: The dry eye measurement tools included the Schirmer test, conjunctivocorneal staining, the tear film break-up time, as well as the administration of a dry eye symptoms questionnaire. Happiness was measured by the Subjective Happiness Scale. Main Outcome Measures: Dry eye examination parameters, dry eye symptoms questionnaires, and the Subjective Happiness Scale score. Results: Of the 672 workers, 561 (83.5%) completed the questionnaires and examinations. The mean Subjective Happiness Scale score was 4.91 (SD = 1.01). This score was inversely correlated with the dry eye symptom score (r = -0.188, p