In this Article

• What is the structure of the normal lung?
• What processes determine normal function of the lung?
• What are the abnormalities (diseases) in smoker's lung?
• What happens to the lung in emphysema?
• How does emphysema come about?
• Why does smoker's lung look black?
• What happens to the airways in chronic bronchitis?
• Are smokers with COPD predisposed to developing pneumonia?
• What about lung cancer in smokers?
• Are any of the pulmonary consequences of smoking reversible?
• From what do smokers die?
• Smoker's Lung: Pathology Photo Essay Glossary
• Smoker's Lung: Pathology Photo Essay Index

Are any of the pulmonary consequences of smoking reversible?

First, the bad news is that emphysema is not reversible. But now, the good news! If a person stops smoking, the inflammatory changes (chronic bronchitis) in the airways probably will go away. Furthermore, when a person stops smoking, the risk of developing lung cancer decreases, although it never goes back to normal. In other words, the risk of cancer in ex-smokers is less than in smokers, but remains greater than in non-smokers.

From what do smokers die?

Remarkably, despite a wealth of information on death rates (mortality) from cigarette smoking, little information is available on the specific causes of death in smokers. Smokers with COPD can die from lack of oxygen (hypoxia) in the tissues of the body. The hypoxia occurs because there is so little functioning lung left and/or the effort of breathing is so great that affected individuals just stop breathing from exhaustion. Other important causes of death in smokers include lung infection (pneumonia), lung cancer, cancers of the digestive, urinary, and genital systems, and leukemia. Indeed, because smoking can cause cancer in so many organs, 30% of all cancer deaths can be related to cigarette smoking.

Nevertheless, because smoking is such a powerful risk factor for the development of coronary atherosclerosis (hardening and blockage of the arteries of the heart), heart disease is by far the most common cause of death in smokers. (See the article: Heart Attack Pathology: Photo Essay.) Moreover, since autopsies are done in less than 10% of patients who die in hospitals and less than 1% of patients who die in nursing homes, we really can't prove why most smokers die. You see, even though a clinician is often correct about the cause of a person's death, only an autopsy can be definitive. (Please see the article on Autopsy.)