What are nasal polyps?

Nasal polyps are soft, painless, non-cancerous growths on the lining of your nasal passages or sinuses. They hang down like teardrops or grapes in your nasal passages. They may make you feel like you have a cold. If the polyps are small, you may not have many symptoms. Larger growths or groups of nasal polyps can block your nasal passages, causing you to lose your sense of smell or have trouble breathing or frequent infections. The blocked nasal passages and sinuses can also worsen asthma symptoms.

Researchers don’t fully understand what causes nasal polyps. Inflammation is believed to be a major factor, but scientists are unsure why inflammation triggers polyps in some people and not in others. It may be due to a person’s immune system response or chemical markers in their mucous membranes.

Symptoms of nasal polyps

Some of the symptoms of nasal polyps include:

• a stuffy or blocked nose and feeling congested
• trouble breathing with your nose (because the polyps block your airflow and do not allow mucus from your nose to drain)
• frequent sneezing
• postnasal drip
• a runny nose
• trouble with your sense of smell (anosmia) – it may be decreased or absent
• loss of sense of taste

If the polyps in your nose are small, you may not have many symptoms. If you have larger nasal polyps, you will likely have more symptoms. If your polyps are not removed, they can lead to worsening asthma symptoms if you already have asthma.

How are nasal polyps diagnosed?

Your doctor may be able to make a diagnosis based on your answers to questions about your symptoms, a physical exam and an examination of your nose using a lighted instrument. Other methods used for diagnosis are listed below.

Nasal endoscopy. Using a narrow tube with a lighted magnifying lens or tiny camera, your doctor can examine inside your nose and sinuses.

CT scan. CT scan images can help your doctor see the size and location of polyps and the amount of inflammation.

Allergy tests. Allergy tests can show whether allergies are contributing to chronic inflammation. With a skin prick test, drops of allergens are pricked into the skin of your forearm or upper back to see if they cause an allergic reaction on your skin.

Nasal polyps and asthma

While overall prevalence of nasal polyps is low (about 4% of the population), it is more common in people with asthma. For example, one study found that 16.5% of people with asthma over 40 years of age have nasal polyps.

Nasal polyps are a subgroup of chronic rhinosinusitis. But not all people with this condition will develop nasal polyps. Chronic rhinosinusitis is defined as having two or more symptoms that persist for more than 12 weeks, including facial pain/pressure, nasal discharge with pus, nasal obstruction and decreased sense of smell (anosmia) during chronic inflammation and nasal polyps. While about 7% of people with asthma have chronic rhinosinusitis with nasal polyps (CRSwNP), 20-60% of people with CRSwNP have asthma.

Studies have shown that patients with nasal polyps and asthma have more severe asthma than those who don’t have polyps. For example, one study found that people with asthma and nasal polyps have increased airway obstruction, more inflammatory cells and reduced asthma control compared to those without nasal polyps.

Treating nasal polyps

Patients with asthma and CRSwNP report it affects their quality of life, including physical functioning, body pain and vitality. But there are treatments that can bring relief.

Nasal spray. One of the most common ways to treat nasal polyps is with nasal corticosteroid spray, which helps shrink polyps and reduce irritation.

Oral medication. Oral corticosteroids can also reduce the size of polyps, but if taken for a long period, they can cause adverse effects, including cataracts, osteoporosis, increased risk of infection and elevated blood sugar, which can lead to diabetes.

Surgery. If using a nasal spray or oral steroids does not help, endoscopic surgery can remove the polyps and fix the sinuses to help prevent more polyps.

Newer ways to treat polyps

A newer way to shrink or reduce polyps is to use biologic therapies, which are also used to treat moderate to severe asthma. For nasal polyps, biologics may be used when the usual medications or surgery have not been successful. While oral corticosteroids affect the whole body (which is why they can cause widespread side effects), biologics are more precise, targeting specific cytokines that circulate in your body and drive inflammation and the development of polyps.

Biologics to treat nasal polyps

One biologic that doctors in Canada can prescribe to help shrink nasal polyps is called dupilumab. Dupilumab attacks cytokines called IL-4 and IL-13, which are involved in inflammation that lead to nasal polyposis. Other biologics that are being studied as possible treatments for nasal polyps are omalizumab and mepolizumab. Canadian doctors also use these biologics to treat asthma.