CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Chronic Obstructive Pulmonary Disease

Chronic Obstructive Pulmonary Disease

Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a leading cause of illness, disability, and death in the United States. COPD refers to a group of diseases, including emphysema, chronic bronchitis, and in some cases asthma, that cause airflow blockage and breathing-related problems. COPD can cause coughing, wheezing, shortness of breath, chest tightness, and other symptoms. Cigarette smoking is a key factor in the development and progression of COPD. Other risk factors include: exposure to air pollution in the home and workplace, genetic factors, and respiratory infections. About 12 million Americans have been diagnosed with COPD, and another 12 million Americans are considered likely to have the disease, but it is undiagnosed (MacNee & Rennard, 2009).

Etiology

Most patients with chronic airflow limitations are or were smokers, and their lung disease is a direct consequence of the toxic effects of tobacco smoke on the lung. A smaller number have been exposed to environmental tobacco smoke (second-hand smoke) or to dusts, chemicals, or smoke at work, or to environmental pollution. People who genetically lack the enzyme a-1 antitrypsin also develop COPD, typically at an earlier age than smokers (in their 40s instead of their 50s or 60s).In the U.S. millions of people have COPD. About a half million Americans are admitted to hospitals each year with exacerbations of the disease (Silverman, 2002).

COPD

This condition is likely in any current or ex-smoker aged over 35 who has any combination of breathlessness, chest tightness, wheeze, sputum production, cough, frequent chest infections and reduced ability to exercise. Many patients with COPD also have asthma, but the pure form of the latter is different because it is reversible - that is it gets better and worse with time (asthma attacks) or can be reversed by bronchodilators. In particular, in COPD the cough tends to be persistent and productive of sputum, the shortness of breath gets steadily worse over years and - unlike asthma - patients do not feel worse at night. The term has come to include chronic BRONCHITIS, EMPHYSEMA, and chronic ASTHMA, where the airflow into the lungs is obstructed (Sandford and Silverman, 2002).

Chronic bronchitis is typified by chronic productive cough for at least three months in two successive years (provided other causes such as TUBERCULOSIS, lung cancer and chronic heart failure have been excluded). The characteristics of emphysema are abnormal and permanent enlargement of the airspaces (ALVEOLI) at the furthermost parts of the lung tissue. Rupture of alveoli occurs, resulting in the creation of air spaces with a gradual breakdown in the lung's ability to oxygenate the blood and remove carbon dioxide from it (see LUNG). Asthma results in inflammation of the airways with the lining of theBRONCHIOLES becoming hypersensitive, causing them to constrict (Mannino and Akinbami, 2002). The obstruction may spontaneously improve or do so in response to bronchodilator drugs. If an asthmatic patient's airway obstruction is characterised by incomplete reversibility, he or she is deemed to have a form of COPD called asthmatic bronchitis; sufferers ...