Causes
Cigarette smoking is the number one cause of emphysema. Although smoking
has decreased in North America since 1964, it's still a major concern among
young people. 20% of people who have smoked a pack of cigarettes a day for 20
years have obstructed airways. Five out of every six lung cancer victims are
smokers. A huge majority of emphysema sufferers have smoked heavily in the past.
A burning cigarette emits over 4,000 different chemicals, many of which are
carcinogenic (cancer-causing) or otherwise toxic to living tissue.
Infections of the respiratory tract can also destroy lung tissue and thus contribute
to the development or worsening of emphysema. Likewise, having emphysema increases
the likelihood of infection.
Heredity is occasionally a factor in emphysema. Carriers of a specific genetic
abnormality called homozygous 1-antitrypsin deficiency are at high risk
of developing emphysema. However, it is relatively rare and accounts for less
than 1% of cases. If you have 1-antitrypsin deficiency, it's vital not to smoke.
Aging naturally brings changes to the lungs and air sacs even in non-smokers.
The loss of elasticity can eventually become severe enough to be classified
as emphysema. Air pollution can also irritate the lungs and cause emphysema,
although pollution alone is rarely the cause.