More screen time mean less protein in tears
There are limited reports on the relationship between mucin 5AC (MUC5AC) a protein that is secreted by cells in the upper eyelid and helps to make up a part of the mucus layer or “tear film” which keep the eyes damp.
There are limited reports on the relationship between mucin 5AC (MUC5AC) concentrations in tears, working hours, and the frequency of ocular symptoms in visual display terminal users. In this new study Dr. Yuichi Uchino, MD, PHD, Research Fellow in Ophthalmology at Schepens Eye Research Institute, Boston, and lead author along with colleagues had examined these relationships among patients with dry eye disease (DED) and individuals serving as controls.
This study included 96 young and middle-aged Japanese office workers (60 men and 36 women) and both eyes of the workers were studied. Participants that worked in a company that used visual display terminals filled out questionnaires about their working hours and the frequency of ocular symptoms such as itchiness. Dry eye disease was diagnosed as definite or probable, or it was not present.
Definite dry eye disease was found in nine participants and probable dry eye disease in 55 participants.
People without dry eyes have around 8.2 nanograms of MUC5AC per milligram of tear film and those with dry eyes3.5 nanograms. Among participants those who looked at computer screens at an average of eight hours daily secreted about 6.8 nanograms and those who spent less time looking at their screens secreted more of the protein such as those who spent less than five hours a day looking at their screen secreted 9.6 ng/mg.
Among participants 71% of men and 14% of women reported ocular problems such as blurred vision, irritation and burning. Eye problems were linked to poor quantity or quality of eye film
According to Dr. Uchino, "To understand patients' eye strain, which is one of major symptoms of dry eye disease, it is important that ophthalmologist pay attention to MUC5AC concentration in tears,” as related by Reuters News.
The researchers write” The data obtained in the present study suggest that office workers with prolonged VDT use, as well as those with an increased frequency of eye strain, have a low MUC5AC concentration in their tears. Furthermore, MUC5AC concentration in the tears of patients with DED may be lower than that in individuals without DED.”
This study is published in JAMA Ophthalmology June 05, 2014.