Smoking - What Causes Copd: Respiratory Health

Content provided by the Faculty of the Harvard Medical School

Smoking

The inflammation that smoking causes in the respiratory system (see "How does COPD develop?") triggers many physiological processes that damage the airways and degrade lung tissue. Although being a smoker is the biggest risk factor for COPD, passive smoking can contribute to the disease, too. Even if you are not a smoker, you may be at some risk from inhaling the cigarette smoke of a spouse, parent, or another smoker with whom you live or spend a lot of time for many years.

Chronic obstructive pulmonary disease is more than four times as prevalent among smokers as among nonsmokers: It affects about 14% of smokers and just 3% of nonsmokers, according to a survey by the Centers for Disease Control and Prevention. In addition, smokers are 10 times more likely to die from COPD. An intriguing question is why even more smokers don't get COPD. The fact that a relatively small percentage of smokers is affected strongly suggests that there are genetic factors that influence which smokers get the disease and which don't.

Last updated:	May 23, 2007