Eye Conditions Linked to Sleep Apnea

Sleep apnea is a sleep disorder in which a person can have hundreds of involuntary breathing pauses per night. This leads to an array of symptoms and a risk for developing health complications, including certain eye disorders. Early diagnosis of these disorders is essential, because it can prevent and even restore vision loss in some cases.

This article reviews the various eye conditions linked to sleep apnea.

The Link Between Sleep Apnea and Eye Health 

Sleep apnea can cause certain ocular (eye) changes that lead to a range of eye disorders.

Some of the eye disorders linked to sleep apnea are caused by hypoxia (low oxygen) that results from the sleep apnea itself. When a person with sleep apnea stops breathing, the oxygen saturation in their blood drops. When they start breathing again, the oxygen will quickly increase. This constant fluctuation of oxygen levels can impact the pressure in the eyes and lead to an inflammatory response.

Other eye disorders may result from a common sleep apnea treatment, continuous positive air pressure (CPAP) devices.

CPAP is the gold standard, first-line treatment for sleep apnea. However, it can be irritating to the eyes for some people.

If a healthcare provider suspects that CPAP treatment is contributing to a patient's eye issues, they may recommend other solutions, such as a better fitting mask or other sleep apnea treatments.

Eye Conditions Found in Sleep Apnea Patients 

Dry Eye Syndrome

Dry eye syndrome is one of the more common but least serious eye conditions found in people with sleep apnea. However, dry eye can still be extremely disruptive to a person's quality of life, so it's important to address it promptly.

While many people with sleep apnea are grateful for CPAP treatment, one side effect is that air can leak from the mask and enter the eyes. Continuous air flow into the eyes for eight hours of sleep every night can lead symptoms of dry eye syndrome, including:

• Irritation
• Teariness
• Itching
• Burning

Sometimes, dry eye syndrome can be treated by adjusting the fit of the CPAP mask, switching to a nasal mask if appropriate, or changing sleeping position.

In other cases, preservative-free artificial tear drops or ointment may be prescribed to help maintain moisture in your eyes overnight.

Floppy Eyelid Syndrome

Floppy eyelid syndrome is associated with obstructive sleep apnea. In fact, eye specialists view floppy eyelid syndrome as a warning sign for undiagnosed sleep apnea and may order a sleep study when it is identified.

In people with floppy eyelid syndrome, their upper lid has unusual laxity, meaning it might appear loose, overstretched, elastic, or be able to turn inside out. This can lead to symptoms of eye irritation and dry eye.

It's unclear exactly why floppy eyelid syndrome and sleep apnea are linked. Theories include a weak tarsal plate secondary to obesity (which is also linked to sleep apnea), or central nervous system malfunction.

Papilledema

Papilledema is swelling of one or both optic nerve discs. The optic nerve disc is where the optic nerve enters the back of the eye.

Swelling can potentially lead to blindness. As such, it's very important to address the cause of this swelling.

Papilledema can be caused by idiopathic intracranial hypertension (IIH), which means increased spinal fluid pressure around the brain in the absence of a brain tumor, a bleed, or other known disorder.

The American Academy of Ophthalmology notes a connection between sleep apnea and IIH. There can be a relative increase in body carbon dioxide levels as a result of interrupted breathing from sleep apnea.

When an eye specialist notices papilledema, they will do an extensive evaluation to find the cause of the papilledema and may recommend a sleep study to assess for sleep apnea.

Nonarteritic Anterior Ischemic Optic Neuropathy (NAION)

Nonarteritic anterior ischemic optic neuropathy (NAION) is sometimes called an "eye stroke."

In NAION, there is ischemia (a loss of blood flow) to the optic nerve, which can result in loss of vision. This is painless, sudden, and usually occurs in one eye.

About 70%-80% of people with NAION have sleep apnea. The exact mechanism of how sleep apnea may cause NAION is not well understood, but as with other eye conditions, it may be linked to:

• Hypoxia
• Oxidative stress
• Fluctuating ocular pressure

Diagnosing and treating sleep apnea will not cure the vision loss caused by NAION. However, it can prevent NAION vision loss from occurring in the other eye, as well as reduce symptoms and risks of other serious health complications.

Retinal Vein Occlusion (RVO)

Retinal vein occlusion (RVO) is another cause of vision loss. In RVO, there is a blockage in the small veins that carry blood away from the retina. This blockage can result in blindness.

RVO is more prevalent among people who have obstructive sleep apnea. Estimates suggest that 37%–77% of people with RVO also have sleep apnea.

It is believed that the breathing interruptions from sleep apnea lead to hypoxia, increased intracranial pressure, and inflammation, which can thereby cause blockages in the small veins around the eyes.

Glaucoma

Glaucoma is more common among those with obstructive sleep apnea than it is in the general public. Additionally, according to a recent study, severity of sleep apnea is associated with severity of glaucoma.

People with glaucoma have high pressure in the eye, which can cause damage to the optic nerve. This results in loss of peripheral vision. Over time, the visual field gets smaller and smaller and eventually may lead to total blindness.

It is believed that sleep apnea leads to glaucoma through recurrent hypoxia (low oxygen) and oxidative stress, which damages the optic nerve.

Research also shows that CPAP treatment may trigger glaucoma damage, so those people using CPAP should be regularly screened for glaucoma.

Central Serous Retinopathy (CSR)

Central serous retinopathy (CSR) occurs when there is a buildup of fluid under the retina, which can lead to retinal detachment. This can lead to:

• Blind spots
• Blurry central vision
• Seeing color incorrectly
• Distorted vision

Multiple studies have shown that CSR is more common in people with sleep apnea than the general public. Research also shows that CSR symptoms can rapidly improve when someone starts CPAP treatment. 

Seeing an Eye Specialist 

Based on their eye exam findings, eye specialists can refer you to a sleep study and sleep apnea diagnosis. They are also available for more frequent vision and eye health screenings if you are already diagnosed with sleep apnea.

Some eye specialists that you might encounter include:

• Ophthalmologist: This is an eye doctor who specializes in the medical and surgical care of the eye and vision. This specialty requires a doctor of medicine (MD) degree.
• Optometrist: This is an eye doctor who diagnoses and treats eye disorders, and is considered the primary eye healthcare provider. Optometrists hold a doctor of optometry (OD) degree.

Seeing an eye specialist is essential because they can help restore your vision, prevent further vision loss, diagnose sleep apnea, or refer you to other healthcare providers.

Eye Tests

If you have sleep apnea, you should see an eye specialist regularly for routine eye exams. During this appointment, they may take some tests, like a tonometry, to examine the pressure in your eyes. This helps screen for glaucoma, which can be associated with sleep apnea.

They may also use a retinal camera to examine the back of your eye for the presence or possibility of eye diseases.

Your eyes will be physically examined, likely while your specialist is wearing an ophthalmoscope to help them view your eyes better. You may also be asked questions about any symptoms of dry eyes.

Additionally, if your eye specialist suspects sleep apnea, they will ask you questions about your symptoms. This might include a standardized self-answer test like the Epworth Sleepiness Scale or Berlin Questionnaire to assess your level of daytime sleepiness.

Treatment 

The exact treatment for each eye disorder associated with sleep apnea will differ. For many of them, part of treatment may include diagnosing and treating sleep apnea. Depending on the eye condition, vision and other symptoms might improve once the sleep apnea is under control.

Some treatments for sleep apnea include:

• CPAP device
• Bilevel positive airway pressure (BiPAP) device
• Custom-fit dental device
• Surgery
• Positional therapy
• Lifestyle changes, such as losing weight, quitting smoking, or eliminating alcohol

Summary

Multiple eye disorders are linked to sleep apnea. This is due to the physiological effects of interrupted breathing, including hypoxia (low oxygen), increased skull and ocular pressure, inflammation, and more. Some of the eye conditions associated with sleep apnea include dry eye syndrome, floppy eyelid syndrome, papilledema, eye stroke, and glaucoma.

A Word From Verywell

In some cases, treating your sleep apnea correctly can improve your vision significantly, or prevent you from further vision loss. In other cases, an eye disorder may lead your eye specialist to investigate and diagnose sleep apnea. It's important to be aware that sleep apnea is linked to certain eye disorders, just as it is with other serious health complications. If you have sleep apnea and are concerned about your vision, be sure to talk to your eye specialist.