Staring at screens all day linked to changes in eye secretions
A broker monitors share prices while trading at a brokerage firm in Mumbai May 13, 2014. REUTERS/Danish Siddiqui/Files
Jun 16, 2014
By Kathryn Doyle
NEW YORK (Reuters Health) – Office workers who spend long hours looking at computer screens have changes in their tear fluid similar to people with the disease known as dry eye, according to a study from Japan.
The protein MUC5AC, secreted by cells in the upper eyelid, makes up part of the normally occurring mucus layer, or “tear film,” that keeps the eye moist. But study participants with the most screen time had MUC5AC levels nearing those of people with diagnosed dry eye.
“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,” said Dr. Yuichi Uchino, an author of the new study.
Uchino is an ophthalmologist at the School of Medicine at Keio University in Tokyo.
“When we stare at computers, our blinking times decreased compared to reading a book at the table,” he told Reuters Health by email.
People staring at screens also tend to open their eyelids wider than while doing other tasks, and the extra exposed surface area in addition to infrequent blinking can accelerate tear evaporation and is associated with dry eye disease, he said.
Dry eye may be chronic for some but can be managed with over the counter or prescription eye drops.
Past research suggests that up to 5 million men and women over age 50 in the United States suffer from dry eye disease, the researchers write in their report. In Japan, tens of millions of people report some dry eye symptoms, often associated with computer work, they add.
The study team tested the tears from both eyes of 96 Japanese office workers, about two-thirds of them men, and measured how much of the total protein content of the tears was MUC5AC.
PN 
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