What is the Link Between Sleep Apnea and Glaucoma?

Thursday, August 25 2016 | 00 h 00 min | Vision Science

New research from Hokkaido University in Japan measured the increase in eye pressure of apnea patients during sleep and found a surprising correlation with glaucoma.

People with obstructive sleep apnea syndrome (OSAS) are more likely to suffer from strokes and cardiovascular disease. They are also ten times more likely to suffer from glaucoma.

Published in Investigative Ophthalmology and Visual Science, the researchers developed a method of continuously measuring intraocular pressure (IOP) during the night, without waking the patient, using a contact lens sensor. Using this sensor they were able to monitor the effects of apnea-hypopnea events (pauses in breathing or overly shallow breathing) on IOP values.

The sleep study was conducted on seven males with sleep apnea (mean age 52) and no history of eye disease. Patients diagnosed with glaucoma were specifically excluded from this study. These patients experienced between 20-80 apnea-hypopnea events per hour (events which last for at least 10 seconds, long enough to affect blood oxygenation). An apnea-hypopnea index (AHI) over 30 is classified as severe sleep apnea.

The overnight contact lens monitoring found that IOP levels “significantly declined in immediate response to apnea events, suggesting an elusive link between OSAS and glaucoma in terms of how OSAS contributes to the pathogenesis of glaucoma as a proposed risk factor.”

This research reinforces that there is a strong correlation between pressure within the chest cavity and intraocular pressure, though they caution that studies with larger sample sizes are needed to determine the mechanism of OSAS-related glaucoma.

Full text of paper: http://iovs.arvojournals.org/article.aspx?articleid=2525820