Are Sleep Apnea and Dry Eye Linked?

Obstructive sleep apnea (OSA) affects about 14 percent of men and 6 percent of women in the United States. The most common treatment is a continuous positive airway pressure machine (CPAP). Users receive constant airflow through a tube that stretches from a mask placed over the nose to the device. While it is very effective in treating sleep apnea, it can cause chronic dry eye (CDE).¹

What is chronic dry eye?

Tears protect our eyes by keeping them wet and smooth. They can help focus your eyes and protect you from some infections and eye irritants. When your eyes do not make enough tears or your tears do not work correctly, you have dry eyes.²

Every time you blink, you spread a tear film across your cornea. There are 3 layers in the tear film: oily, watery, and mucus. If any of the layers do not work right, it can affect the moisture in your eye and cause dry eye.³

Symptoms of CDE include:³

• Stinging or burning
• Blurred vision
• Scratchy, gritty feeling
• Red or irritation
• Eye fatigue
• Problems driving at night

An eye doctor (ophthalmologist) usually diagnoses CDE using tests to measure the quality and thickness of your tears and how fast you produce tears.

What is obstructive sleep apnea?

OSA is when the airway in the back of the throat becomes blocked by soft tissue and causes you to momentarily stop breathing. When oxygen levels fall, your brain wakes you, and you start breathing again. You might stop breathing hundreds of times each night.⁴

Symptoms of OSA include:⁴

• Snoring
• Daytime sleepiness
• Irritability
• Morning headaches, sore throat, or dry mouth
• Limited attention span

Many people are unaware they stop breathing during the night. In many cases, their partner notices or awakens through the night from loud snoring or snorting.

How does obstructive sleep apnea cause dry eyes?

The CPAP machine is considered the “gold standard” of treatment for OSA. These machines work by providing a constant flow of air that prevents the throat from closing.⁵

However, using a CPAP can cause dry eyes. One study showed that about 50 percent of users had some eye problems, including chronic dry eye. The severity of CDE directly correlated with the severity of sleep apnea. One possible reason is that air can leak out of the side of the mask when it does not properly fit. This can cause the air from the CPAP to blow directly into the eyes.¹

What you can do

If you use a CPAP and often wake up with dry eyes, the first step is to talk to your doctor. Discuss ways you can decrease the risk of dry eyes. Some ways include:^6,7

• Consider a different type of mask. Full face masks cover your nose and mouth and might work well if you breathe through your mouth during your sleep. Some masks have nasal pillows that fit under your nose. Other people might find this type constricting because it has straps across your forehead and cheeks.
• Work with your CPAP supplier to fit the mask to your face and head. Besides different types of masks, there are different sizes. Have your CPAP supplier correctly fit the mask and show you how you can adjust it at home.
• Adjust your mask. Make adjustments to ensure your mask does not sit too high on your nose. If air does leak, a high-positioned mask can direct the air into your eyes.
• Consider a nasal CPAP mask if you need a higher-pressure setting. Higher pressure settings can cause air leaks. This type of mask covers your nose but not your mouth. It is somewhere between a full mask and a nasal pillow type.

Working with your doctor can help you keep your sleep apnea well-controlled while reducing your risk of chronic dry eye.