Chronic Obstructive Pulmonary Disease
(COPD, Chronic Obstructive Lung Disease, COLD)

• Chronic obstructive pulmonary disease (COPD) is characterized by chronic obstruction of airflow out of the lungs.
• COPD is comprised primarily of two related diseases - chronic bronchitis and emphysema.
• In chronic bronchitis there is inflammation and swelling of the lining of the airways that leads to their narrowing and obstruction.
• In emphysema there is permanent enlargement of the alveoli due to the destruction of the walls between alveoli.
• COPD causes poor gas exchange in the lungs leading to decreased oxygen levels in the blood, increased carbon dioxide levels, and shortness of breath.
• The major cause of COPD is smoking. Other less common causes include air pollution, repeated lung damage from infections, and inherited disease (alpha-1 antitrypsin deficiency).
• Treatment consists of cessation of smoking, medications to open the airways and decrease inflammation, prevention of lung infections, oxygen supplementation, and pulmonary rehabilitation.

Chronic obstructive pulmonary disease (COPD) is comprised primarily of three related conditions, 1) chronic bronchitis, 2) chronic asthma, and 3) emphysema. In each condition there is chronic obstruction of the air flow through the airways and out of the lungs, and the obstruction generally is permanent and may progress over time.

While asthma features obstruction to the flow of air out of the lungs, usually, the obstruction is reversible. Between "attacks" of asthma the flow of air through the airways typically is normal. These patients do not have COPD. However, if asthma is left untreated, the chronic inflammation associated with this disease can cause the airway obstruction to become fixed. That is, between attacks, the asthmatic patient may then have abnormal air flow. This process is referred to as lung remodeling. These asthma patients with a fixed component of airway obstruction are also considered to have COPD.

Patients with COPD are often classified by the symptoms they are experiencing at the time of an increase of the symptoms of the disease. For example, if a patient is experiencing primarily shortness of breath, they may be referred to as a patient with emphysema. If the patient is primarily experiencing a cough and mucus production, he or she is referred to as having chronic bronchitis. Actually, it is preferable to refer to these patients as having COPD, since they can experience a variety of lung symptoms.

Source: MedicineNet.com
http://www.medicinenet.com/chronic_obstructive_pulmonary_disease_copd/article.htm