Emphysema is a progressive lung condition that is a form of chronic obstructive pulmonary disease. Smoking is the most common cause of emphysema.
What is emphysema?
Emphysema is a lung condition that causes shortness of breath and a cough. The air sacs in the lungs (alveoli) are damaged. Over time, the inner walls of the air sacs weaken and the lining of the alveoli becomes damaged. This causes a smaller number of larger air spaces instead of normal small ones. The smaller number of larger air sacs causes a reduction in the overall surface area of the lungs. This means that less oxygen can be transferred from the air you breathe in into your bloodstream.
Most people with emphysema also have a condition called chronic bronchitis. Chronic bronchitis causes inflammation in the tubes (called bronchi) that carry the air to and from your lungs. This leads to a persistent cough and further reduces the air that gets down into your lungs. Emphysema and chronic bronchitis are the two conditions that make up chronic obstructive pulmonary disease (COPD).
How common is emphysema?
Emphysema affects about 14 million people in the USA. This includes about 14 out of every 100 white male smokers and 3 out of every 100 white male non-smokers. Slightly fewer female smokers and African Americans are affected.
In the UK it is thought that around 1.2 million people have COPD. This number represents 2 out of every 100 of the whole population, or between 4-5 out of 100 of all people aged over 40.
Who is at risk of having emphysema?
Factors that increase your risk of developing emphysema include:
- Smoking. Emphysema is most likely to develop in cigarette smokers; however, cigar and pipe smokers also are susceptible. The risk for all types of smokers increases with the number of years and amount of tobacco smoked.
- Age. Although the lung damage that occurs in emphysema develops gradually, most people with tobacco-related emphysema begin to experience symptoms of the disease between the ages of 40 and 60.
- Passive smoking. This means breathing in the smoke from someone else's cigarette, pipe or cigar. Being around secondhand smoke increases your risk of emphysema.
- Occupational exposure to fumes or dust. If you breathe fumes from certain chemicals or dust from grain, cotton, wood or mining products, you're more likely to develop emphysema. This risk is even greater if you smoke.
- Exposure to indoor and outdoor pollution. Breathing indoor pollutants (such as fumes from heating fuel), as well as outdoor pollutants (such as car exhaust).
What are the causes of emphysema?
The main cause of emphysema is smoking. Other causes include long-term exposure to irritants in the air, such as marijuana, air pollution, and chemical fumes and dust.
Rarely, emphysema is caused by an inherited deficiency of a protein that protects the elastic structures in the lungs. This condition is called called alpha-1-antitrypsin deficiency.
What are the symptoms?
Emphysema is a long-term condition that usually progresses slowly over a number of years. There may be no symptoms for a long time and you may not know that you have emphysema.
As the shortness of breath and the cough become progressively worse, you will find you will become increasingly less active until even usual daily domestic tasks become very difficult. Emphysema eventually causes shortness of breath even while you're at rest.
What tests are needed?
The most common test used in helping to diagnose the condition is called spirometry. Other tests include a chest X-ray and blood tests to help exclude other serious conditions. Occasionally, a special computerised tomography (CT) scan of the chest - high-resolution CT - is needed.
How is emphysema treated?
The most important part of treatment is to reduce exposure to any cause - particularly to avoid smoking, including passive smoking. The treatment for many people with emphysema is the same as for chronic obstructive pulmonary disease (COPD).
Surgery (such as lung volume reduction surgery or a lung transplant) may be considered for advanced severe emphysema.
An endobronchial valve is an a small one-way valve, which is placed in an airway (bronchus), usually using a bronchoscope. The valve allows air to flow out of the lung when you breathe out but blocks air from entering that lung when you breathe in. This helps to remove the excess air that is trapped in your lungs if you have emphysema. In the UK, the National Institute for Health and Care Excellence (NICE) recommends that endobronchial valve insertion to reduce lung volume can be considered as a treatment option.
What are the complications of emphysema?
People who have emphysema are also more likely to develop:
- Chest infections. These can occur frequently.
- Collapsed lung (pneumothorax). A collapsed lung can be life-threatening in people who have severe emphysema, because the function of their lungs is already so compromised. This is uncommon but serious when it occurs.
- Heart problems. Emphysema can increase the pressure in the arteries that connect the heart and lungs. This can cause failure of the right side of the heart, which pumps blood to the lungs (this condition is called cor pulmonale).
- Large holes in the lungs (bullae). The bullae can be as very large. These bullae reduce the transfer of oxygen into the bloodstream and also increase the risk of a pneumothorax.
Can emphysema be prevented?
This risk of emphysema can be greatly reduced by:
- Not smoking.
- Avoiding passive smoking.
- Wearing a mask to protect your lungs if you work with chemical fumes or dust.
Further reading and references
; NICE Interventional Procedure Guidance, December 2017
; Emphysema. StatPearls Publishing. 2018.
; Endobronchial Valves for Endoscopic Lung Volume Reduction: Best Practice Recommendations from Expert Panel on Endoscopic Lung Volume Reduction. Respiration. 201793(2):138-150. doi: 10.1159/000453588. Epub 2016 Dec 20.
; Cardiovascular function in pulmonary emphysema. Biomed Res Int. 20132013:184678. doi: 10.1155/2013/184678. Epub 2013 Dec 3.