Purpose: To evaluate sleep and mood status in patients with dry eye disease (DED) and analyze the association between sleep quality, mood status, and ocular surface characteristics.
Methods: Consecutive patients with DED (N = 106) and age- and sex-matched healthy controls (N = 50) were enrolled. Tear fluid break up time (TBUT), corneal fluorescein staining, and Schirmer I tests were performed in the order listed here to evaluate dry eye. A visual analog scale was used to assess dry eye symptom severity. All subjects also completed the Pittsburgh Sleep Quality Index (PSQI, scores ≥5.5 indicated poor sleep), Patient Health Questionnaire (scores ≥5 indicated depression), and General Anxiety Disorder Scale (scores ≥5 indicated anxiety).
Results: Mean Pittsburgh Sleep Quality Index global score was significantly higher in patients with DED than that in controls (7.8 ± 3.9 vs. 5.4 ± 3.0, respectively; P < 0.001). Patients with DED demonstrated higher respective depression and anxiety scores compared with controls (P < 0.001 and 0.013, respectively). In the DED group, patients with poor sleep quality had more severe DED indicated by shorter TBUT and lower Schirmer I findings. A significant correlation was found between sleep quality and mood status in patients with DED. Regression analysis revealed that shorter TBUT and lower Schirmer I test results were associated with poorer sleep quality (adjusted p = 0.011 and 0.037, respectively). More severe symptoms of dry eye were significantly associated with a higher level of anxiety in patients with DED (adjusted p = 0.011).
Conclusions: Sleep quality may play an important role in the development of DED by influencing tear secretion and tear film stability and/or by indirectly aggravating anxiety and depression, leading to higher self-reported symptom scores. It is also possible that DED contributes to reduced sleep quality, as well as the development of anxiety and depression.