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Conditions Expert Dr. Otis Brawley Chief Medical Officer,
American Cancer Society

Expert answer

Dear Pamela,

Chronic obstructive pulmonary disease, or COPD, is a disease that truly negatively affects quality of life. Patients with COPD are prone to asthma-like wheezing, breathlessness, chest tightness and coughing that can occur in episodes caused by chromic inflammation. They're also prone to viral and bacterial infections.

It is the fourth most common cause of death in the United States, killing an estimated 120,000 people each year.

While COPD is most noted for episodes of shortness of breath and wheezing, the disease is typically slowly progressive and persistent. Medical treatment can be successful in relieving symptoms and reducing the severity of exacerbations.

Treatment is with inhaled bronchodilators, steroids to reduce inflammation and other oral medications.

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Early diagnosis and good treatment are important as they can reduce the number and severity of exacerbations and prolong survival. Some people can live with this condition for several decades.

More than 80% of patients with COPD have a history of cigarette smoking. A few patients have it because of chemical inhalation exposure. Most are overweight or obese. Weight loss can also occur in severe COPD and is a sign of severe disease with a poor prognosis.

At one time, we distinguished different types of COPD, emphysema and chronic bronchitis. All patients with COPD have an element of each, although one component will usually predominate in the individual patient.

Chronic bronchitis is defined by a chronic cough that produces sputum. Emphysema is defined by enlargement and destruction of the airspaces in the lung.

When the physician examines a patient with very severe COPD one finds decreased breath sounds, wheezes, crackles at the lungs, and distant heart sounds. The patient's diaphragm in limited in movement, meaning the patient cannot take in deep breaths. In extremely severe disease, the chest size is increased.

Patients lean forward to use all the muscles of the chest and neck to bring air in. COPD can progress to cause heart failure, as the right side of the heart cannot pump blood into the damaged lungs.

Could your job be hurting your lungs?

Physicians use pulmonary function tests to assess the severity of COPD. These are tests to measure how fast it take a patient to fully exhale air, how much air he can exhale in one second, how much air he can inhale. X-ray and especially CT scans can also be used to assess damage to the lungs.

The arterial blood gases are a series of blood tests to determine how much oxygen and carbon dioxide is in the blood. As the disease worsens oxygenation goes down and carbon dioxide levels rise. Blood gas abnormalities acutely worsen during COPD exacerbations and often worsen during exercise and sleep.

Because most patients have a significant smoking history, most patients have many of the other illnesses associated with smoking, especially cardiovascular disease. These patients also have high risk for smoking related malignancies.

Unfortunately, poor lung function often interferes with or prevents treatment of the other diseases.