Known to many as chronic bronchitis or emphysema, Chronic Obstructive Pulmonary Disease (COPD) is estimated to affect 32 million persons the United States - it is also the fourth leading cause of death there. Patients typically have symptoms of both chronic bronchitis and emphysema, but the classic triad also includes asthma. Most of the time COPD is secondary to tobacco abuse, but other more rare conditions, such a cystic fibrosis, may be contributing factors. Men are more likely to have COPD than women and COPD occurs predominantly in individuals over 40. COPD is a mixture of 3 separate disease processes that together form the complete clinical picture. These processes are chronic bronchitis, emphysema and, to a lesser extent, asthma. While each case of COPD is unique in the blend of processes, two main types of the disease are recognized.

Chronic Bronchitis - "Blue Bloaters"
Chronic bronchitis plays the major role in this type and is defined by excessive mucus production with airway obstruction and notable enlargement of mucus-producing glands.

Damage to the airway lining impairs the miniature ciliary hairs located there which usually help clear bacteria and mucus. Inflammation and secretions provide the obstructive component of chronic bronchitis. In contrast to emphysema, chronic bronchitis is associated with a relatively undamaged pulmonary capillary bed. Emphysema is usually present to a variable degree.

As the disease progresses, these patients develop signs of right-sided heart failure and are known as "blue bloaters".

Emphysema - "Pink Puffers"
The second major type is that in which emphysema is the primary underlying process. The physiology of emphysema involves the gradual destruction of the small air sacs where gas diffusion takes place, and of the pulmonary capillary bed, leading to a decreased ability to oxygenate blood. The body compensates with lowered cardiac output and more rapid breathing. Eventually, these patients develop muscle wasting and weight loss and are identified as "pink puffers".

Patients with COPD are susceptible to many factors that can lead to an acute deterioration. Aggressive and prompt intervention may be the only action that prevents respiratory failure. Being obese can aggravate COPD.