Chronic bronchitis is a type of chronic obstructive airway disease (abbreviated as COPD). People with COPD have limitations in the flow of air through their airways. Chronic bronchitis is an ongoing inflammation of the breathing tubes that produces large amounts of discolored sputum.
What is going on in the body?
Chronic bronchitis results from long-term exposure of the airways to irritants. These irritants include tobacco smoke, air pollution, and chemicals, any of which cause the airways to secrete excess mucus and to become inflamed. With time, the inflammation becomes widespread, the cells lining the airways change, and the glands that produce the mucus become enlarged.
Inflammation and excess mucus combine to cause a cough that produces discolored sputum, or phlegm, almost every day. The World Health Organization (WHO), has recently developed a classification system for the severity of chronic bronchitis and other forms of COPD.
There are four stages of severity, as outlined below:
Stage 0, or at risk for COPD. These people have chronic cough and sputum production. Their lung function tests are still normal.
Stage I, or mild COPD. Individuals in this group have mild limitations in their airflow and changes in their lung function tests. They generally have chronic cough and sputum production.
Stage II, or moderate COPD. People at this stage have worsening of airflow that leads to shortness of breath with exertion. Their lung function tests show marked limitations.
- Stage III, or severe COPD. Individuals at this stage have severe airflow limitations that impair their quality of life. Their lung function tests are markedly abnormal. They often require home oxygen therapy.
What are the causes and risks of the condition?
Cigarette smoking is the most common cause of chronic bronchitis. The risk goes up with the amount of tobacco smoked and the number of years of smoking. Chronic bronchitis is most common in countries where smoking is prevalent. Passive smoking, or exposure to secondhand smoke, also increases a person's risk for chronic bronchitis.
Other risk factors for chronic bronchitis include the following:
- indoor air pollution, such as smoke from home cooking or home heating fuels
- occupational dusts and chemicals
- outdoor air pollution, such as motor vehicle exhaust fumes
- previous viral infection of the lungs
- untreated lung infections
What can be done to prevent the condition?
Many risk factors for chronic bronchitis can be completely eliminated. Those who smoke need to quit, using any of a number of available means. Sources of indoor air pollution can be identified and removed. It is also important to avoid secondhand smoke.
How is the condition diagnosed?
Diagnosis of chronic bronchitis begins with a medical history and physical examination. A persistent cough which produces discolored yellowish, gray or green sputum is one of the main signs of bronchitis.
Lung function tests can identify chronic bronchitis in Stage 0, even before the individual has symptoms. Lung function tests measure how much air a person can take in with a deep breath, and how fast the person can push the air back out of the lungs. The healthcare professional may also order a chest X-ray and blood tests.
Long Term Effects
What are the long-term effects of the condition?
Chronic obstructive pulmonary diseases, including chronic bronchitis, are the fourth leading cause of death in the world. The long-term effects depend on how severe the disease is when diagnosed and if a reduced exposure to the lung irritant occurs. The most effective treatment is quitting smoking. This will typically result in a modest improvement, or at least little or no further decline, in function.
People with chronic bronchitis have a higher mortality than those with normal lung function. Causes of death include respiratory failure, lung infections such as pneumonia and influenza, and other diseases related to smoking such as cancer, heart disease, and stroke.
What are the risks to others?
Chronic bronchitis is not contagious and poses no risk to others.
What are the treatments for the condition?
WHO has identified the following four components for management of chronic bronchitis:
- assessing and monitoring of the disease
- managing exacerbations, or episodes where symptoms are worse
- managing stable chronic bronchitis
- reducing the person's risk factors
Assessment and monitoring
Assessment and monitoring of the disease incorporates the following steps:
- doing a medical history and physical exam to evaluate symptoms
- identifying people at risk for chronic bronchitis, even if they have no symptoms
- performing lung function tests to measure airflow limitations
Reducing risk factors
Reducing the person's risk factors includes the following recommendations:
- Avoid vigorous outdoor exercise when air quality is poor.
- Eliminate sources of indoor pollution, such as wood-burning stoves.
- Limit exposure to secondhand smoke.
- Reduce occupational dusts and chemicals.
- Stop smoking, if the person smokes.
Managing stable chronic bronchitis
Management of stable chronic bronchitis includes the following:
- Learn to identify and avoid risk factors.
- Learn to identify problems and seek appropriate treatment.
- Take medications as directed.
Recommendations for management of chronic bronchitis are broken down by the severity of the disease. Recommendations for Stage 0 chronic bronchitis include the following:
- Get a flu vaccine once or twice a year.
- Get the pneumonia vaccine at least once
- Identify and eliminate risk factors.
- Use antibiotics only for bacterial infections, but not for chronic bronchitis itself.
Recommendations for Stage I chronic bronchitis are the same as those for Stage 0. In addition, people with Stage I chronic bronchitis should use short-acting bronchodilators as needed. Bronchodilators relieve coughing and shortness of breath by opening the airways. In general, WHO recommends inhaled bronchodilators rather than oral medications.
Recommendations of Stage II chronic bronchitis include the recommendations from Stage I. These additional measures are recommended for times when symptoms are present.
- Use long-acting bronchodilators on a regular basis.
- Use inhaled glucocorticosteroids, for people with significant cough or shortness of breath.
- Participate in a pulmonary rehabilitation program that uses teaching and exercise to improve lung function.
WHO recommendations for Stage III chronic bronchitis are as follows:
- Use long-acting bronchodilators regularly.
- Take short-acting bronchodilators as needed.
- Seek treatment for complications, such as pneumonia.
- Participate in a pulmonary rehabilitation program.
- Use oxygen as needed.
- Discuss surgical options with the healthcare professional.
Managing worsening symptoms
People with chronic bronchitis may have worsening, or exacerbation, of symptoms when they develop a respiratory infection. Symptoms may also be worsened by cigarette smoke, as well as other factors.
WHO guidelines for management of worsening symptoms:
- Increase the dose and/or frequency of inhaled bronchodilators.
- Take oral glucocorticosteroids to decrease airway swelling.
- Take antibiotics for bacterial infection.
- Take oxygen by mask or cannula.
WHO recommends the use of noninvasive positive pressure ventilation as a way to decrease the need for intubation and mechanical ventilation, and to shorten the hospital stay.
What are the side effects of the treatments?
Bronchodilators may cause an increased heart rate and blood pressure. Oral glucocorticosteroids can cause increased risk for infection, high blood sugar, and osteoporosis. Antibiotics can cause rash, stomach upset, and allergic reaction.
What happens after treatment for the condition?
Early diagnosis of chronic bronchitis and effective treatment can slow its progression. People who eliminate risk factors and follow treatment guidelines have better outcomes. Those who continue to smoke may be increasingly disabled by breathing problems and complications of chronic bronchitis.
How is the condition monitored?
Chronic bronchitis is monitored through regular visits to the healthcare professional. Lung function tests can be used to monitor limitations in airflow. The healthcare professional should be notified if there is low grade fever that lasts more than three days, fever of 101 degrees F for any length of time, breathlessness, coughing up bloody yellowish or green sputum, or of any other new or worsening symptoms.