Last reviewed by Faculty of Harvard Medical School on January
24, 2013 By Harvey B. Simon, M.D. Harvard Medical School Chronic
obstructive pulmonary disease (COPD) is the fourth leading cause
of death in the United States. It's also the only disease among
the top 10 killers that is seeing an increase in deaths each
year. About 15 million Americans suffer from COPD. Men are
affected about twice as often as women because male smokers have
outnumbered female smokers. COPD is not curable, but it is
treatable. Lifestyle changes and medication can help people cope
with chronic lung disease and live longer, fuller lives. But as
you'll see, most cases of COPD can be prevented. Back to top
What Is COPD? COPD refers to chronic illnesses that block the
flow of air and make breathing difficult. The two major forms of
COPD are chronic bronchitis and emphysema. In both, narrowed air
passages or bronchi make it hard to exhale. (Bronchi are wider
during inhalation and narrow during exhalation.) Narrowed
bronchi also cause as