The Influence of Time Spent Viewing the Video Display Terminal, Sleep, Anxiety and Depression on the Thickness of the Lipid Layer of the Tear Film.

Objective: To investigate the influence of time spent viewing a video display terminal (VDTt), sleep, anxiety, and depression on the thickness of the lipid layer of the tear film (LLT).

Methods: This is a cross-sectional study. A total of 102 patients were enrolled. Their ocular surface disease index (OSDI), Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, Pittsburgh Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale anxiety subscale (HADS-A), and depression subscale (HADS-D) were recorded. The LLT, meibomian gland secretion quality, tear film break-up time (TBUT), conjunctival hyperemia grade, corneal staining score, and VDTt were also evaluated. Spearman analysis was used to analyze the correlation. The patients were divided into the thinner LLT group (LLT < 75 nm) and the thicker LLT group (LLT ≥ 75 nm). The Mann-Whitney U test was used to analyze the characteristics and to compare the two groups. The receiver operating characteristic (ROC) curve was used to predict the relationship between VDTt and LLT.

Results: Spearman correlation analysis showed a significant positive correlation between TBUT and average LLT, and significant negative correlations between mean LLT and OSDI, SPEED, meibomian gland secretion quality, conjunctival hyperemia, corneal staining, VDTt, PSQI, and HADS-A. In comparison to the thick LLT group, the thin LLT group had a worse OSDI score, shorter TBUT, longer VDTt, worse PSQI and HADS-A scores. The ROC curve indicated that the optimal cutoff value for using VDT to predict LLT less than 75 nm is 8.25 hours.

Conclusion: The thinner LLT had worse questionnaire scores and signs related to dry eye, which indicates that a thinner LLT is more prone to causing dry eye. Using VDTt for more than 8.25 hours is more likely to induce thinning of the LLT, thereby increasing the risk of dry eye. Patients with a sleep disorder and anxiety are more susceptible to thinning of the LLT, suggesting that they are prone to developing dry eye syndrome.