While cancer and COPD are closely related, many other complications brought on could be Heart Disease, Pneumonia, Pneumothorax (collapsed lung), Sleep Disorders, or Pulmonary Embolism (blood clot in the lungs) (14). They have a very high risk especially for pneumonia and acute bronchitis (2).
Emphysema's vast majority of cases are brought on by smoking (6). It is estimated that cigarette smoking causes 82% of all COPD (2). It does not develop suddenly, but comes on gradually (15), usually requiring 20-30 years of smoking (1). Cigarette smoking damages the cells in the lungs (3). Smoking causes lung cancer, heart disease, emphysema, and contains carbon monoxide according to the surgeon generals warning on each pack of cigarettes (12). The other 18% are caused by air pollution, occupational exposure to irritants (such as firemen, possibly a viral infection (9) and there is a rare heredity form of Emphysema caused by a protein deficiency (14) called alpha 1-antitrypsin deficiency (AAT) (8). Most always cigarette smoking is combined in these cases. Between 80 & 90% of all people who have emphysema are heavy smokers (17). It is estimated 50,000 to 100,000 Americans today live with this deficiency (15). AAT is referred to sometimes as early-onset Emphysema because it may begin as early of the ages of late 20's early 30's (15). .
There can be no symptoms in the early stages because symptoms develop gradually over the years. Shortness of breath that increases in severity increasing over several years may be a sign of Emphysema (8). Shortness of breath, a chronic mild cough and sometimes weight loss occur (2). Wheezing is usually the first obvious sigh that there may be something wrong with the lungs (3). But eventually the shortness of breath will become constant (3). The technical term used for mucus is sputum, which refers to secretions from the lungs (17). Other signs may be a heavy cough that won't go away or a lot of mucus from the lungs that doesn't clear up (1), chronic cough (7), occasional recurrent infections of the lungs or bronchial tubes (8), coughing up clear mucus (sputum) often occurs or shortness of breath with little or no exertion (2).