Chronic Obstructive Pulmonary Disease is characterized by an insufficient flow of air out of the lungs. COPD is not a single disease. Usually two diseases are involved: chronic bronchitis and emphysema. In some cases chronic asthmatic bronchitis results in COPD. COPD is the 4th leading cause of death in the United States. Tobacco is the #1 risk factor.
Acute bronchitis, often called a "chest cold", usually occurs as part of an upper respiratory infection. When acute bronchitis does not clear quickly but, instead persists or recurs over and over, it is known as chronic bronchitis. Gradually, the bronchi become scarred and narrowed thereby obstructing airflow. The person experiences daily coughing and breathing difficulty. Some improvement is possible with treatment. Susceptibility to pneumonia increases and over time it is possible to develop a chronic obstructive condition known as pulmonary emphysema in which movement of air in and out of the alveoli is significantly reduced. 14 million people in the United States suffer from chronic bronchitis.
Continual breathing difficulty, chronic wheezing and coughing characterize emphysema. It is an irreversible disease; however, some relief of symptoms can be achieved with treatment. 1.9 million people in the United States have emphysema.
Chronic asthmatic bronchitis can also result in an obstructive disease and results in permanent changes in the structure and function of the lungs. A person with chronic asthmatic bronchitis may also develop pulmonary emphysema. Some improvement may be possible with treatment.
In some cases respiration is limited by other factors such as the structure of the chest cavity. Aging is associated with some decrease in lung function. The work of breathing declines due to the shortening of the ventilator chest muscles; the abdominal wall weakens and allows descent of the diaphragm; elasticity of lung tissue is reduced; there is a progressive loss of resilience in the bone and cartilage of the rib cage. All of these factors present a valid argument for a lifetime of following a good general conditioning program.
