Chronic obstructive pulmonary disease, or COPD, is characterized by abnormalities in the lungs that make it difficult to exhale normally. Generally, two distinct diseases are involved: emphysema and chronic bronchitis. According to the World Health Organization (WHO), 75% of deaths from COPD that occur in developed countries are directly related to smoking tobacco.
Emphysema and chronic bronchitis cause excessive inflammatory processes that eventually lead to abnormalities in lung structure that permanently obstruct airflow (hence the term "chronic obstructive"). A recent study shows that adults with asthma are 12 times more likely to develop COPD than those who do not have the condition.
Incidence and Prevalence
The American Lung Association and the World Health Organization track respiratory disease and mortality rates related to tobacco use.
United States - Approximately 16.4 million people suffer from this disease. According to the American Lung Association, approximately 14 million people suffer from chronic bronchitis, the seventh leading chronic condition in the United States. There are an estimated 1.9 million people suffering with emphysema. Of these, 55.5% are men and 44.5% are women. Between 1982 and 1995 emphysema increased in women by 14.8%, probably due to the increased rate of smoking among women. An estimated 50,000 to 100,000 people, primarily of northern European descent, have AAT deficiency emphysema. COPD is the fourth leading cause of death in the United States. In 1996, approximately 100,360 people died as a result of COPD.
Russian Federation - Tobacco is a major cause of male mortality in the Russian Federation. In 1995, 280,000 people died from tobacco use. Tobacco caused approximately one-third of all male deaths in 1995 and 18% of all deaths. Three-fourths of those men were under 70 years of age.
United Kingdom and Northern Ireland - Although tobacco use has declined dramatically in the U.K., the death rate attributable to COPD and tobacco use was 63 per 100,000 men and 25.1 per 100,000 women in the early 1990s.
China - According to the WHO, tobacco consumption in China doubled between 1965 and 1990. In the mid-1990s, smoking caused far more deaths from COPD than from cardiovascular disease. China has the world's highest rate of mortality attributable to tobacco use.
Risk Factors
Tobacco use is the number one risk factor for COPD and heavy smokers are at greatest risk. Cigarette smokers are at greater risk than cigar and pipe smokers. All smokers are at greater risk than lifelong nonsmokers.
Having alpha-1-antitrypsin (AAT) deficiency, also called familial emphysema, is another risk factor. People with familial emphysema have a hereditary deficiency of alpha-1-protease inhibitor. When there is a deficiency of AAT, the activity of elastaseÂ--an enzyme that breaks down elastinÂ--is not inhibited and elastin degradation occurs unchecked. Individuals with a severe genetic deficiency of AAT usually have symptoms by the time they reach early middle age. It is critical that people with this deficiency never smoke. Approximately 1% to 3% of all cases of emphysema are due to AAT deficiency.
Asthma also increases the risk for developing COPD later in life.
