The Link Between Excess Mucus Production and COPD

Phlegm and coughing are signs of chronic bronchitis

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Why does chronic obstructive pulmonary disease (COPD) cause increased mucus production? It's a common question if you've been diagnosed with CODP—especially if you've also been told you have chronic bronchitis.

Excess mucus is sometimes referred to as "chronic mucus hypersecretion" or "chronic sputum production." In COPD the condition is called "chronic bronchitis." Chronic bronchitis is defined as "the presence of a chronic, productive cough and sputum production for at least three consecutive months in two consecutive years." 

Causes of Mucus Production in COPD

Some patients with COPD have increased mucus production and secretion because of an over-abundant amount of mucus-producing cells (called goblet cells) and oversized mucus glands in their airways compared with healthy people.

This results in a chronic cough. A cough is the body's defense mechanism developed in an attempt to clear the airways of sputum, the thick liquid, or phlegm, that comes up from your lungs when you are sick. Unfortunately, people with COPD also have difficulty clearing the excess mucus because of their ineffective cough and other aspects of their condition. 

Here are some of the factors that can contribute to mucus overproduction and hypersecretion in COPD:

  • cigarette smoke exposure
  • acute and chronic viral infection
  • bacterial infection

Smoking is the biggest factor in chronic bronchitis. Studies show that cigarette smokers with both chronic bronchitis and a limited airflow have an increased number of goblet cells and inflammatory cells in their airway.

How Too Much Mucus Can Affect Your Health

If you have COPD, chronic bronchitis can impact your health. Here are a few ways:

  • The health of your lungs. Chronic mucus production is related to a decline in lung function over time.
  • Your quality of life. Research shows that COPD patients with chronic bronchitis have more physical activity limitations and worse quality of life than those who don't have excess mucus and cough.
  • A number of flare-ups. Chronic bronchitis may increase the number of COPD exacerbations and hospitalizations. 
  • Your risk of death. Some studies suggest that chronic bronchitis is a risk factor for respiratory-related mortality and mortality from all causes, although more research is needed. 

Even if you don't have COPD yet, chronic bronchitis might be a warning sign. Research shows that chronic bronchitis is a predictor of COPD. In one study, young adults who had a chronic cough and phlegm but normal lung function had almost a three-times higher risk of developing COPD than those who didn't have chronic bronchitis. 

Treatment of Chronic Bronchitis

Treatment is focused on helping you produce and secrete less mucus and clear more of it out of your airway. If you smoke, studies show that quitting smoking can help clear up your cough. Quitting smoking is the best thing you can do for your chronic bronchitis and COPD.

People with chronic bronchitis usually use inhalers - often more than one - to ease airway swelling and open the airways. The oral corticosteroid prednisone is often prescribed for chronic bronchitis, as well. 

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Article Sources

  • Chronic Bronchitis. MedlinePlus. February 17, 2016.
  • Patient information: Chronic bronchitis (The Basics). UpToDate.
  • Ramos, F.L., Krahnke, J.S. and Kim, V. Clinical issues of mucus accumulation in COPD. Int J Chron Obstruct Pulmon Dis. 2014; 9: 139–150.