The effect of day-long mask wearing on non-invasive break-up time.

PURPOSE: This study aimed to investigate the effect of day-long face mask wearing on non-invasive tear break-up time (NI-BUT) in health care staff due to working schedules. METHODS: Seventy-four right eyes of 74 participants were included in the study. Participants completed the Ocular Surface Disease Index (OSDI) questionnaire, and NI-BUT measurements were performed between 08.30-09.00 and 16.30-17.00 h. Participants with an initial NI-BUT measurement below 17 s were classified as group-1, and those over 17 s were classified as group-2. NI-BUT changes during the day and correlation to age, gender, and OSDI results were evaluated. RESULTS: Thirty-eight women and 36 men, with a mean age of 30.9 ± 8.5 years, were included in the study. The mean OSDI score of the participants was 28.6 ± 17.1. NI-BUT means of group-1 at baseline and 8th hour were 11.4 ± 3.3 and 7.9 ± 3.6 s, respectively, and the mean NI-BUT at the 8th hour was statistically significantly lower than the baseline (p < 0.0001). Also, 24.2% (8 people) of those in group-2 had the 8th-hour NI-BUT value fallen into the measurable range (below 17 s). No significant correlation was found between the decrease in NI-BUT value and age, gender, and OSDI (p = 0.08, p = 0.3, and p = 0.2, respectively). CONCLUSION: The use of face masks throughout the day leads to a significant reduction in NI-BUT, regardless of age, gender, and OSDI score. Prolonged use of face masks should be considered as a risk factor for evaporative dry eye disease.