CPAP's Benefits for Asthma

Continuous positive airway pressure (CPAP)—which uses a machine that pushes pressure into your airways to prevent their inward collapse—is the primary treatment for obstructive sleep apnea (OSA). While designed to address the nighttime interrupted breathing characteristic of OSA, CPAP has the added potential of helping improve your asthma symptoms if you have both conditions.

If you have asthma, you might also have sleep apnea—having both conditions is rather common. In one study, 58% of people with moderate asthma had sleep apnea, as did 88% of people with severe asthma.

It's possible that your asthma (not just your sleep apnea) could be improved by using CPAP, and this treatment could be a missing piece to an effective asthma management plan. Ensuring that sleep apnea doesn't go untreated can also help prevent complications of this serious condition, including increased risk of high blood pressure and diabetes.

Sleep Apnea's Effect on Asthma

With sleep apnea, your upper airway closes repeatedly while you sleep. Your body wakes you up or brings you up into a lighter stage of sleep to get you breathing again.

You may wake up:

• Gasping for air
• Choking
• Gagging
• Coughing

This sleep disruption leaves you tired, even when you get plenty of sleep. But sleep apnea can also lead to other complications that may seem less obvious, such as high blood pressure, diabetes, heart disease, and exacerbated chronic health conditions—like asthma.

Sleep apnea worsens asthma symptoms in a number of ways, including the following.

• Research suggests that several mechanical features of sleep apnea may inflame and constrict the bronchial tubes (airways), worsening asthma symptoms.
• The vibration from snoring associated with untreated sleep apnea may damage the soft tissues around your upper airway and nasal passages. The resulting narrowing of the small airways leads to more irritation and contraction of the smooth muscles.
• When apnea makes you stop breathing, it changes the activity of the vagus nerve, which triggers receptors in the central airways to constrict the bronchial tubes and causes an asthma attack.
• Breathing interruptions are suspected of increasing airway resistance and making you less likely to wake up when an asthma attack begins.

Widespread Inflammation

Sleep apnea may cause inflammation throughout the body, including what is already present in the lungs due to asthma. And breathing interruptions can lead to oxidative stress

.Inflammation also contributes to weight gain and obesity, which further worsens asthma (and sleep apnea).

Damage to soft tissues causes further inflammation.

Acid Reflux

Acid reflux during sleep is well-known to cause and worsen nighttime asthma symptoms.

Sleep apnea can cause and/or worsen acid reflux, probably by decreasing the ability of the esophageal sphincter to keep acid in the stomach.

Endothelial Dysfunction

Since airflow is decreased during sleep apnea, this leads to low oxygen levels in the bloodstream and strain on the heart and blood vessels—what's known as endothelial dysfunction.

Bronchial tube constriction can occur along with this because:

• Endothelial growth factors in your circulatory system may play a causal role in both asthma and sleep apnea. These growth factors are hypothesized to increase bronchial inflammation and airway hyperresponsiveness.
• The altered sleep architecture of sleep apnea prevents the heart from relaxing normally while you sleep, which can contribute to or worsen congestive heart failure. Congestive heart failure further increases airway hyperresponsiveness, which increases asthma symptoms.

How CPAP Helps

CPAP is the gold-standard treatment for obstructive sleep apnea. When you sleep, you wear a mask connected to a machine that pushes a constant flow of pressurized air into your airways.

This helps keep the airways open so that you do not have gaps in your breathing throughout the night.

CPAP also reverses some of the other harmful effects of sleep apnea:

• It lowers the inflammatory chemicals caused by sleep apnea, leading to less inflammation in the lungs and in the body overall.
• It increases airflow within the airways, leading to better oxygenation of the lungs and decreased contraction of the smooth muscles around the airways.
• It improves acid reflux by helping the sphincter muscles in the esophagus stay closed to keep acid from coming up.

These very same factors play a role in asthma, making a reduction in asthma symptoms a logical—though perhaps surprising—bonus of CPAP treatment in those with both conditions.

Do You Need CPAP?

CPAP is not used for the sole purpose of treating asthma. So, if you have been evaluated for sleep apnea and have not been given the diagnosis, CPAP is not right for you.

However, if you have been diagnosed with sleep apnea, CPAP may be recommended. In fact, it will likely be prescribed in all cases with the exception of those that are mild and able to be managed with lifestyle changes, like weight loss.

If you have asthma and have not yet been diagnosed with sleep apnea, but experience the following symptoms, it is worth seeing your healthcare provider:

• Chronic snoring
• Choking or gasping during sleep
• Pauses in breath while sleeping
• Bruxism (teeth grinding)
• Dry throat/mouth upon awakening
• Irritability, poor concentration or attention

Shared Risk Factors

Asthma and sleep apnea have some risk factors in common, which is likely responsible for some of the overlap between them.

If you have asthma, the likelihood of you also having sleep apnea is higher if either of these apply to you.

Obesity

There is a bit of a circular relationship between these conditions when it comes to obesity.

• Obesity is associated with higher levels of inflammation, and additional inflammation in the airways exacerbates asthma.
• Asthma may also contribute to weight gain by making it harder to exercise. The excess weight compresses your lungs, making breathing more difficult and sleep apnea more likely.
• Untreated sleep apnea can lead to sleep deprivation, which can contribute to weight gain and/or make weight loss more difficult. This can interrupt nighttime breathing and worsen asthma symptoms.

Studies show that losing just 10% of your body weight can improve symptoms of both asthma and sleep apnea.

Smoking

Smoking increases inflammation, obstruction, and resistance in the airways.

Asthma symptoms become more frequent and more severe as a result, and sleep apnea symptoms are exacerbated as well.

Other Sleep Apnea Treatments

The complex interplay of these two conditions means that treating one is likely to make the other one better, so you have extra incentive to stick to the treatment regimens recommended by your healthcare provider(s).

However, not everyone can tolerate a CPAP. If you struggle with it, ask your healthcare provider about alternative treatments such as:

• Positional sleep aids to prevent rolling onto your back
• Dental devices or oral appliances
• Weight loss (lifestyle changes, medication-assisted, bariatric surgery)
• An implantable device

Uvulopalatopharyngoplasty (UPPP or UP3) is a surgical option that involves removing the tonsils and part of the soft palate and uvula. UPPP may be useful in some cases and is recommended for patients who aren't overweight or obese. It should be noted, though, that some people who have the surgery end up needing a CPAP anyway.

How Can Asthma Make Sleep Apnea Worse?

Given connections like increased inflammation and constriction of the airways, yes—it can. Beyond these, though, asthma may make sleep apnea worse in several other ways.

So, while adequately managing sleep apnea may help your asthma symptoms, the reverse may be true as well.

Changes Due to Corticosteroids

Corticosteroids, in inhaled and oral (tablet or liquid) form, are a common treatment for asthma, especially when symptoms are moderate to severe. One study found that 95% of people with poorly controlled asthma taking corticosteroids had sleep apnea.

Researchers concluded that corticosteroids increase airway collapsibility and lead to sleep apnea symptoms, and their conclusion has been supported by further studies.

Researchers suspect the drug narrows the upper airway by:

• Causing fat deposits in the area
• Weakening the muscles that dilate the airway
• Contributing to obesity

Nasal Obstruction

People with asthma are especially likely to have allergies, non-allergy rhinitis, and nasal polyps—all of which can make it harder for you to breathe through your nose.

That leads to higher negative pressure when you inhale, which makes the collapse of your airway and apnea symptoms more likely. One study showed that nasal congestion from allergies was associated with a 1.8-fold increase in the risk of sleep apnea.

A Word From Verywell

Both asthma and sleep apnea are serious, potentially life-threatening illnesses. When you have them both, it's especially important to be diligent about your treatments.

If you have trouble using your CPAP or your asthma isn't well-controlled, talk to your healthcare provider about what other options are available.