Emphysema and Chronic Obstructive Pulmonary Disease (COPD)
COPD stands for Chronic Obstructive Pulmonary Disease. Over 15 million Americans have been diagnosed with COPD. Evidence suggests that another 15 million have COPD but remain undiagnosed. COPD is presently the third leading cause of death in this country and the 2nd leading cause of disability. Most COPD is related to cigarette smoking, but recent evidence suggests that 25% of those with COPD never smoked. Increasingly environmental factors are felt to play a role in the development and worsening of COPD. There is also an inherited form of COPD called alpha-1 antitrypsin deficiency.
All COPD is not the same. There are those with more of a chronic bronchitic form and some with a more emphysematous form. Emphysema is a progressive, destructive lung disease in which the walls between the tiny air sacs are damaged. As a result, the lungs lose their elasticity and exhaling becomes more and more difficult. Air remains trapped in the overinflated lungs leading to progressive shortness of breath.
Exacerbations, or flares of disease, are critically important. People with frequent exacerbations (2 or more a year), have more rapid deterioration in lung function, more frequent hospitalizations, and higher mortality. Treating and preventing exacerbations are critical factors in managing COPD.
COPD and asthma are both obstructive lung diseases marked by shortness of breath but asthma is by definition reversible while in COPD the airflow obstruction is either irreversible or only partly reversible. The mainstay of therapy in asthma is inhaled corticosteroids while in COPD it is long acting bronchodilators. Over time some asthmatics may develop an irreversible component, a variant of COPD. Because both are common diseases they can occur together. Estimates suggest that as many as 20% of COPD patients have ACOS, the asthma/COPD overlap.