Ophthalmic disorders linked to sleep disorders, finds research

Rochester, MN-Sleep disorders can be indicators of various unrecognized eye disorders, according to the results of a literature search reported in the November issue of Mayo Clinic Proceedings.

Obstructive sleep apnea (OSA), a potentially serious sleep disorder that occurs when throat muscles relax and block the airway, afflicts more than 12 million people.

Many studies have determined that OSA is an independent risk factor for the development of several medical conditions, including high blood pressure. The vascular system in eyes sometimes can be affected.

"Given these known physiologic consequences of sleep disorders, it is not surprising that important associations exist between ophthalmologic and sleep disorders,” said lead author E. Andrew Waller, MD, pulmonologist and sleep specialist, Mayo Clinic in Rochester, MN.

Among the findings on sleep disorders related to ophthalmologic disorders:

• Floppy eyelid syndrome: This disorder causes eyelids to evert spontaneously during sleep, resulting in excessive watering, stickiness, discomfort, and blurred vision. Although not a serious medical problem, this syndrome can signal that a person also has OSA, which can lead to more significant health problems.

• Glaucoma: This condition is the second most common cause of blindness and the most common cause of irreversible blindness. OSA is linked to two forms of this disease-primary open-angle glaucoma and normal-tension glaucoma. The severity of glaucoma appears to correlate with the number and duration of apnea episodes in patients with OSA.

• Nonarteritic anterior ischemic optic neuropathy (NAION): Research shows an increased incidence of OSA in people diagnosed with NAION. This condition is characterized by the sudden painless onset of vision loss in one eye, often noticed upon awakening. Up to 6,000 patients annually in the United States are diagnosed with this condition, which can cause irreversible vision loss.

• Papilledema: People with OSA may have a higher incidence of papilledema,. Swelling typically occurs due to increased pressure within the skull and can lead to progressively worsening vision and, in some cases, blindness.

According to Dr. Waller, knowing the links between these eye conditions and OSA may hasten early diagnosis and appropriate treatment.

"Our understanding of the mechanisms that link these disorders is minimal," Dr. Waller said. "However, the recognition of these associations is important for primary-care physicians, ophthalmologists, and sleep physicians. For patients with OSA, a routine eye examination to evaluate for early signs of glaucoma, particularly in the setting of visual loss or change, should be recommended. Patients with ophthalmologic diseases known to be associated with sleep apnea should be screened clinically for sleep apnea and referred to a sleep center if signs or symptoms are present."