What causes emphysema?
Cigarette smoking is the major cause of emphysema, accounting for more than 80 percent of all cases. Emphysema occurs most often in people older than age 40 who have smoked for many years. Long-term exposure to secondhand smoke also may play a role. Smoking stresses the natural antioxidant defense system of the lung, allowing free radicals to damage tissue down to the cellular level. When cigarette smoke is inhaled, 80 to 90 per cent remains in the lungs and causes
irritation, increased mucus production and damage to the deep parts of the lungs. Eventually mucus and tar clog up the air tubes, causing chronic bronchitis and emphysema.
People who a deficiency of a protein called alpha-1 antitrypsin (AAT) are at a higher risk of developing severe emphysema. Alpha-1 antitrypsin deficiency (AAT deficiency) is an inherited condition and occurs in varying degrees. The deficiency leads to A1AD-related emphysema when the liver produces insufficient AAT to control a natural enzyme known as neutrophil elastase. Though neutrophil elastase plays an important role in fighting bacteria and cleaning up dead lung tissue, it eventually causes irreversible damage to the alveoli by damaging or destroying their elastic fibers if there is not enough AAT to neutralize it. For AAT-deficient individuals who smoke, the risk of developing emphysema is much greater than for the general population. A1AD-related emphysema usually strikes people in their thirties or forties and is very rarely seen in children.
Among other causes of emphysema are industrial pollutants, aerosol sprays, non-tobacco smoke, internal-combustion engine exhaust, and physiological atrophy associated with old age (senile emphysema). Physical damage caused by an accident and followed by scarring can give rise to scar emphysema; severe respiratory efforts can rupture alveoli in cases of near suffocation, whooping cough, labor (child-bearing), and acute bronchopneumonia. Tuberculosis and asthma can also give rise to lung overstretching, severely damaging the elastic fibers of the alveoli walls and bringing on emphysema. High altitude is associated with higher death rates among those suffering with COPD, but is not a proven causative factor at this time. Areas of high poverty also experience higher mortality rates among those suffering from chronic obstructive airway disease, possibly a reflection of inadequate medical care.
More information on emphysema
What is emphysema? - Emphysema is a lung disease that reduces the ability of the lungs to expel air, a process which depends upon the elastic properties of the lungs.
What causes emphysema? - Cigarette smoking is the major cause of emphysema. Among other causes of emphysema are industrial pollutants, aerosol sprays, non-tobacco smoke.
What're the risk factors for emphysema? - The primary risk factor for the development of emphysema is tobacco abuse. Air pollution is another risk factor for emphysema.
What are the complications of emphysema? - Emphysema patients are at increased risk of contracting recurrent respiratory infections and lung cancer. Emphysema is a very serious disease.
What are the symptoms of emphysema? - Symptoms of emphysema include shortness of breath on exertion, unexplained weight loss, increased chest size, wheezing or labored breathing.
How is emphysema diagnosed? - Diagnosis of emphysema begins with a medical history and physical examination. Lung function tests can identify emphysema in Stage 0.
What's the treatment for emphysema? - No treatment can reverse or stop emphysema, but steps can be taken to relieve symptoms, treat complications and minimize disability.
How to prevent emphysema? - Many risk factors for emphysema can be completely eliminated. The best method to prevent emphysema is to avoid smoking.