Does nasal congestion cause asthma?

The following was originally published on July 25, 2011 at myasthmacentral.com.  

The Link Between Nasal Congestion and Asthma

As far back as the 19th century asthma experts have observed the link between asthma and nasal congestion.  Recent studies seem to support this link.  While studies are limited, they seem to show nasal congestion might be a trigger and a cause of asthma.

So let's investigate the evidence and see if we can come to a conclusion.

The two main causes of nasal congestion in asthmatics are:

• Sinusits: According to Mayo Clinic, it's swelling of the nasal sinuses that "interferes with drainage and causes mucus to build up."  If it becomes persistent it may result in infections and other complications.  If it lasts longer than 12 weeks it's called chronic sinusitis.  About 15 percent of Americans have it, yet 70 percent of child asthmatics and 26 percent of adult asthmatics have it. It's often referred to as a cold that won't go away.
• Rhinitis:  Nasal allergies or hay fever.  If left untreated it can lead to sinusitis and otitis media. Studies show 75 percent of asthmatics have allergies.  If rhinitis leads to sinusitis it's referred to as rhinosinusitis.

For simplicity purposes, we'll lump sinusitis and rhinitis together. 

The Mayo Clinic lists the following symptoms:

• Difficult to breathe through nose
• Facial pain
• Headache
• Nasal drainage
• Loss of sense of smell and/or taste
• Nasal obstruction
• Jaw or teeth pain
• Cough (may get worse at night
• Ear pain (otitis media?)
• Sore throat
• Fatigue
• Fever

According to Asthma for Dummies by Dr. William E. Berger, besides rhinitis, other causes of sinusitis are:

• Viruses (the common cold)
• Bacteria
• Fungus (often results from prolonged systemic corticosteroid use)
• Nasal rebound (overuse of  over the counter decongestants
• Nasal polyps
• Deviated nasal septums (the cartilage the separates the nostrils is crooked)
• Enlarged adenoids
• Other

So why is nasal congestion believed to be linked with asthma?

1.  Observations:  Many asthma experts over the years have observed asthmatics to have nasal congestion, deviated septums, polyps, etc.  Likewise, as nasal symptoms are resolved asthma improves, and as nasal congestion worsens so does asthma.

2.  Recent studies:  They seem to prove what was observed. 

So why would nasal congestion lead to asthma?  There are a couple theories:

1. Nasal drainage:  This is often considered an asthma trigger
2. Nasobronchial reflex:  Irritants that stimulate the upper airway may result in inflammation of the lower airway

The second theory there I learned about through the book Emergency Medicineedited by Barry E. Brenner (NewYork, 1999, page 93).  While I've read theories that propose inflammation of the upper airway may lead to inflammation of the lower just because they are connected, this theory provides a more scientific explanation.

Another theory proposes that if a person is exposed to something that causes airway inflammation (such as nasal drainage), and you're exposed to that something often enough so that the inflammation is ongoing, that inflammation may become permanent and result in hyperresponsive airways (asthma).

So, in essence, by either of the above theories, chronic nasal congestion may lead to asthma.  Then once a person has chronic lower airway inflammation the symptoms of rhinitis and sinusitis trigger asthma.  In this way, nasal congestion acts as both both an asthma cause and trigger.

However, these are just theories.  Now let us consider the evidence.

Several studies showing improved asthma symptoms after sinusitis is treated work to further curiosity about the asthma/ sinusitis link. One more recent Swedish study that links nasal congestion with severe asthma may offer further proof.  The study showed that the more severe asthma becomes the greater the risk for having nasal congestion or sinusitis.

The authors of the book Severe asthma: pathogenesis and clinical management  (New York, 2005, page 346) reported cases of chronic sinusitis among severe asthmatics was as high as 50 percent.  This study once again showed nasal congestion very well might cause worsening asthma.

Acute sinusitis can often be treated with home or over the counter remedies.  Yet if it progresses you should see your doctor to seek medical intervention.  The following sinusitis treatments have been shown by studies to reduce asthma symptoms:

1. Irrigation to reduce congestion (you can use warm water or over the counter medicine)
2. Nasal steroids to reduce nasal inflammation (swelling)
3. Nasal decongestants to decrease nasal stuffiness
4. Antibiotics to fight bacterial infections
5. Antihistamines to stave off the allergic response
6. Surgery to resolve problem. 
7. A combination of the above
8. Other

Most studies confirm asthma symptoms significantly improve when nasal congestion improves.  One study showed that treatment with steroids, antibiotics and nasal decongestants improved asthma symptoms in 80 percent of patients. 

Likewise, another study showed that 65 percent of asthmatics who had surgery to repair their sinusitis had improved asthma as a result.  I had surgery about 15 years ago to repair a deviated septum, and my sinus problems and asthma greatly improved as a result. 

The Mayo Clinic says you should seek medical treatment if your symptoms persist more than a few days or get worse, if you develop a fever, or you observe recurrent sinusitis. 

Trust me, it's worth seeking help.  Before my surgery I pretty much had all the above mentioned symptoms to go along with my hardluck asthma, and tried at one point or another all the remedies to no avail. 

I also have a good friend who had a similar surgery 10 years ago and her hardluck asthma likewise improved. 

You guys can take this information and do with it what you like.  I personally think nasal congestion is one of many causes of asthma, and it's definitely an asthma trigger. What do you think?