Chronic obstructive pulmonary disease, also called COPD, is actually a group of lung diseases. People with COPD have limitations in the airflow through their airways. The limitation usually worsens over time. Lungs of people with COPD become easily inflamed from noxious particles or gases. The airways produce extra mucus, which is coughed up as sputum. Chronic bronchitis and emphysema are two common types of COPD. Chronic bronchitis is an ongoing inflammation of the large airways. Emphysema is a chronic disease in which the tissues of the lungs are gradually destroyed.
What is going on in the body?
Chronic obstructive pulmonary disease is caused by exposure to noxious gases or particles, especially cigarette smoke. Over time, this exposure damages the airways. The airways try to protect themselves by making more mucus. However, the lungs may slowly get damaged from chronic irritation. The increased mucus and lung damage can be permanent.
The World Health Organization (WHO) has recently developed a classification system for the severity 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.
Other risk factors for COPD
Other risk factors for COPD include the following:
* Asthma.
* Hereditary deficiency of alpha-1 antitrypsin, an enzyme involved in lung function.
* Indoor air pollution, such as smoke from home cooking or home heating fuels.
* Low birth weight.
* Occupational dusts and chemicals.
* Outdoor air pollution, such as motor vehicle exhaust fumes.
* Severe childhood respiratory infections
What are the signs and symptoms of the disease?
Typical symptoms of COPD are cough and sputum production. Following are some other symptoms of COPD:
* Shortness of breath, which tends to worsen with exertion.
* Swelling in the legs and feet.
* Wheezing, which is a high-pitched sound made when the person breathes.
How is the disease diagnosed?
Diagnosis of COPD begins with a medical history and physical examination. Lung function tests can identify COPD 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. They also measure how fast the person can push the air back out of the lungs. The healthcare provider may also order a chest X-ray and blood tests.
What can be done to prevent the disease?
Many risk factors for COPD can be completely eliminated. Smoking cessation is vital for those who smoke. Sources of indoor air pollution can be identified and removed. It's important to avoid secondhand smoke.
What are the long-term effects of the disease?
COPD is the fourth leading cause of death in the world. The long-term effects depend on how severe the COPD 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 no further decline in function. People with COPD 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. These include cancer, heart disease, and stroke.
What are the risks to others?
COPD is not contagious. However, people who live with smokers have significant health risks because of their exposure to the smoke.
How is the disease monitored?
COPD is monitored through regular visits with the healthcare provider. Lung function tests can be used to monitor limitations in airflow.
