Sleep is sometimes called shut-eye, and good quality sleep is important for eye health. A recent paper from the Mayo Clinic describes eye conditions associated with sleep disorders, especially obstructive sleep apnea (OSA). Patients with OSA stop breathing for periods of 10 seconds to two minutes while asleep, and may awaken choking in severe cases. The blood oxygen falls to about 90 percent of normal in mild cases, or less than 30 percent in severe cases. The blood pressure spikes to high levels. These changes in blood pressure and oxygen are believed to cause a number of health issues, including the eye conditions reported.
Floppy eyelid syndrome. This was first described in 1981. The eyelids are easily everted (turned inside out), and patients sometimes report waking up with everted eyelids. Other symptoms include watering, stickiness, discomfort, blurred vision, downward pointing eyelashes, and eyelid droop or inversion. Patients often develop conjunctivitis and corneal injury. Almost all (96 percent to 100 percent in reported studies) patients with floppy eyelid syndrome also have obstructive sleep apnea. The cause is not well understood. Researchers suggest mechanical stress from rubbing and stretching of the eyelid against the pillow while the patient is asleep, as well as the stress of low oxygen and spikes in blood pressure.
Glaucoma. Patients with primary open angle glaucoma (the most common type) and normal tension glaucoma were found to have a prevalence of obstructive sleep apnea of 20 percent to 57 percent. The authors recommend that all patients diagnosed with sleep apnea be tested for glaucoma, and vice versa.
Optic neuropathy Up to 6,000 patients per year in the U.S. are diagnosed with nonarteritic anterior ischemic optic neuropathy, and in published studies, 71 percent to 89 percent also have sleep apnea.
Papilledema This is a less common eye condition associated with sleep apnea, but it may lead to blindness. The authors recommend screening sleep apnea patients.
CPAP eye complications. The standard treatment for sleep apnea is continuous positive airway pressure, or CPAP, delivered by a device connected to a face mask or intranasal interface. A poorly fitting mask may blow air into the eyes, causing dry eyes and increased susceptibility to bacterial infection. Retrograde movement of air and mucus from the nasal passage through the tear ducts and into the eyes may also increase the risk of eye infection and corneal damage.
Sleep apnea does not always wake the patient fully, so you may not know you have a mild case. Your eye doctor can detect the possible eye complications in a standard exam.
Sources:
Waller EA et al, “Sleep Disorders and the Eye”, Mayo Clin Proc. November 2008; 83(11): 1251-61.
Linda Fugate is a scientist and writer in Austin, Texas. She has a Ph.D. in Physics and an M.S. in Macromolecular Science and Engineering. Her background includes academic and industrial research in materials science. She currently writes song lyrics and health articles.