Problems with the respiratory system impact a large proportion of our population every year. Common diseases such as colds, flu, bronchitis and sinusitis probably impact virtually every household on an annual basis. These are referred to as upper respiratory disorders, usually not constituting an ongoing health problem.
The COPD Epidemic
Lung diseases that permanently affect our breathing capacity are another matter. Chronic Obstructive Pulmonary Disease (COPD) may be the most common of these; the National Heart, Lung and Blood Institute (NHLBI) estimates that twelve million Americans have been diagnosed with COPD and that there are probably another twelve million who have the disease and don't realize it.
COPD sounds like a generic term, but it has come to be defined by two chronic and permanent conditions. Most lung disorders impact the bronchial air tubes and the air sacs that absorb oxygen at the end of those tubes. The prominent respiratory disorders that are usually the chief components of COPD are emphysema and chronic bronchitis; occasionally asthma will enter the picture. It is difficult to understate the impact this disease is having on the American public. In the year 2000, 119,000 deaths, 726,000 hospitalizations, and 1.5 million hospital emergency departments visits were caused by COPD. Both emphysema and chronic bronchitis are permanent and grow progressively worse, leading to severe debilitation.
Pulmonary symptoms for COPD include:
- The bronchial airways and air sacs lose their elastic quality.
- The walls between many of the air sacs are ruined.
- The walls of the airways swell to become thick and inflamed.
- The airways create more mucus than usual, leading to clogging.
Occupational Lung Disorders
Both emphysema and chronic bronchitis are linked to cigarette smoking. COPD is therefore associated primarily with smoking, although it may also involve other airborne toxins such as asbestos fibers, chemicals and other hazardous material that can be carried in a dust cloud. To the degree that asthma contributes to COPD it can be classified as a condition that is aggravated by occupational exposure to pulmonary toxins.
Occupational lung diseases became more common as industrialization became the mainstay of our economy. They have become more evident as millions of industrial workers have retired from the jobs that drove the 20th century American economy. One hundred years ago it was thought that miners – especially coal miners – were the only workers that developed pulmonary symptoms on the job. Today it is believed that occupational lung diseases are the number one work related illness. Employees in textile mills, in steel mills and auto plants, in chemical plants and in any number of other industrial facilities can and did develop an occupational respiratory disease from daily exposure to airborne irritants and toxins.
Black lung disease, malignant mesothelioma, asbestosis and silicosis are probably the most notorious occupational lung diseases, but several others such as asthma and more minor pulmonary injuries have impacted millions of workers.
Infectious Lung Disorders
Aside from the common cold, influenza and the usual respiratory disorders passed around each year, there are more serious problems that develop with diseases like pneumonia and tuberculosis. These are examples of lung disorders that are a long time in healing and that require extended bed rest. With pneumonia in particular, the pulmonary symptoms are common to so many diseases that often pneumonia will go undiagnosed, attributed to a severe cold or lingering flu.
Bronchitis is an example of an infectious disease that crosses over to a permanent lung disorder when it persists as the result of inhaled toxins or years of smoking and becomes chronic. It is one of the principal components of COPD and does not heal like a bronchial inflammation caused by a virus or by bacteria will.
Diseases of the Lung
Pulmonary fibrosis is a disease that impacts the inner lung tissue. Over time the tissue becomes scarred, thickens with scar tissue and loses its flexibility. The ability of the lungs to absorb oxygen is impaired and breathing becomes difficult. Sometimes pulmonary fibrosis is caused by another disease such as a viral infection or an autoimmune disorder that causes multiple physical symptoms. These conditions are referred to as interstitial lung disease (ILD).
Sometimes pulmonary fibrosis may be caused by a reaction to a prescribed drug. And in tens of thousands of cases there is no evident cause, leading to the diagnosis of idiopathic pulmonary fibrosis, or IPF. There are about 200,000 people in the U.S. with IPF as a primary diagnosis; about 40,000 people die from the disease each year.
A pulmonary embolism is blockage of the pulmonary artery, which can be caused by fatty tissue (heart disease), by a tumor (cancer) or by blood clots traveling to a pulmonary artery from another part of the body – usually the legs. It can be a sudden and very dangerous condition, but is often successfully treated with anti-clotting medication and blood thinners.
There are lists of lung diseases that are not covered here but that fill many medical textbooks. What is important to understand is the fact that many respiratory diseases are caused either by bad habits (smoking, and perhaps alcohol consumption) or by exposure to toxins (asbestos and job-related chemicals, gases or fibers).
- NHLBI, National Institutes of Health, http://www.nhlbi.nih.gov/health/public/lung/copd/
- Centers for Disease Control, http://www.cdc.gov/copd/copdfaq.htm#what
- Ohio State University Medical Center, http://medicalcenter.osu.edu/patientcare/healthcare_services/lung_diseases/lung/occupationallung/Pages/index.asp
- Pulmonary Fibrosis Foundation, http://www.pulmonaryfibrosis.org/ipf
- Mayo Clinic, http://www.mayoclinic.com/health/pulmonary-embolism/DS00429
- American Lung Association, http://www.lungusa.org/lung-disease/list.html
- American Lung Association, http://www.lungusa.org/assets/documents/publications/solddc-chapters/occupational.pdf