Emphysema

What happens in emphysema

Healthy lungs contain about 300 to 500 million air sacs with thin, stretchy walls where oxygen passes into the blood. In emphysema, inflammation and enzymes released in response to smoke break down these walls, so many small sacs merge into fewer large ones. This:

• reduces the surface area for gas exchange, lowering oxygen levels
• destroys the elastic recoil that pushes air out, so air gets trapped
• causes small airways to collapse when you breathe out

The lungs over-inflate, the chest may become barrel-shaped, and breathing takes more effort.

Emphysema vs COPD

COPD is the umbrella term for chronic lung disease with airflow limitation. It includes emphysema (air sac damage) and chronic bronchitis (inflamed airways with daily cough and mucus). Most people with COPD have features of both. For broader information, see COPD.

Causes and risk factors

• Smoking: the cause in most cases. Risk rises with pack-years. Pipe, cigar, cannabis smoking and possibly vaping also harm the lungs
• Alpha-1 antitrypsin deficiency: an inherited lack of a protein that protects the lungs. It causes emphysema at a young age, often in the lower lungs, even in light smokers or nonsmokers
• Secondhand smoke
• Indoor air pollution from burning wood, coal or other biomass fuels for cooking or heating
• Occupational dusts and chemicals
• Childhood lung infections and poor lung growth
• Older age

Symptoms

Symptoms develop slowly, often over years, and are easy to blame on aging or being unfit:

• shortness of breath, first with exertion, later with everyday tasks and eventually at rest
• chronic cough, with or without sputum
• wheezing and chest tightness
• tiredness and reduced exercise ability
• weight loss and muscle wasting in advanced disease
• pursed-lip breathing and using neck and shoulder muscles to breathe
• frequent chest infections

Flare-ups (exacerbations)

A flare-up is a sudden worsening of breathlessness, cough or sputum lasting days, usually triggered by a viral or bacterial infection or air pollution. Flare-ups speed lung decline and may need steroids, antibiotics or hospital care. Having a written action plan and rescue medicines at home helps.

Diagnosis

• Spirometry: the key test. You blow out as hard and fast as possible. A ratio of FEV1 to FVC below 0.70 after a bronchodilator confirms airflow limitation
• Chest CT: shows the type and extent of emphysema and screens for lung cancer
• Chest X-ray: may show over-inflated lungs
• Gas transfer test (DLCO): reduced in emphysema
• Pulse oximetry and arterial blood gases: measure oxygen and carbon dioxide
• Alpha-1 antitrypsin level: recommended at least once for everyone with COPD
• Echocardiogram if pulmonary hypertension is suspected

Stages

Doctors grade airflow limitation using the FEV1, the amount of air blown out in the first second, compared with what is expected:

Treatment is guided by symptoms and flare-up history as well as these grades.

Treatment

Stop smoking

Quitting is the single most effective step at any stage. It slows the loss of lung function to near the normal rate for age. Nicotine replacement, varenicline, bupropion and counseling together give the best success rates.

Inhaled medicines

• Long-acting bronchodilators: LAMA (such as tiotropium) and LABA (such as salmeterol or formoterol), often combined, open the airways and reduce flare-ups
• Inhaled steroids added for people with frequent flare-ups and high blood eosinophil counts
• Rescue inhaler (albuterol) for sudden breathlessness
• Correct inhaler technique matters; ask your pharmacist or nurse to check it

Pulmonary rehabilitation

A structured program of exercise training, breathing techniques and education, usually 6 to 12 weeks. It improves breathlessness, exercise ability and quality of life and reduces hospital admissions.

Other treatments

• Vaccines: flu, COVID-19, pneumococcal, RSV and Tdap
• Oxygen therapy for people with persistently low oxygen; using it for at least 15 hours a day improves survival in severe low oxygen
• Treatment of flare-ups: steroid tablets and antibiotics when indicated
• Roflumilast or azithromycin to prevent flare-ups in selected people
• Alpha-1 augmentation therapy (weekly infusions) for alpha-1 antitrypsin deficiency
• Nutrition support for weight loss

Procedures and surgery

• Endobronchial valves: one-way valves placed by bronchoscope to collapse the most damaged area, helping healthier lung expand
• Lung volume reduction surgery for selected people with upper-lobe emphysema
• Bullectomy to remove large air pockets
• Lung transplant for very severe disease in selected people

Complications

• pneumothorax (collapsed lung) from ruptured air pockets
• cor pulmonale: right-sided heart failure from pulmonary hypertension
• respiratory failure
• frequent chest infections and pneumonia
• osteoporosis, anxiety and depression
• higher risk of lung cancer

Life expectancy and outlook

Emphysema cannot be cured, and the outlook depends on severity, smoking status, flare-up frequency, oxygen levels, body weight and exercise ability. People with mild disease who stop smoking may have a near-normal life expectancy. Severe disease shortens life, but treatment, rehabilitation and oxygen therapy improve quality of life. Palliative care supports people with advanced disease.

Frequently asked questions

What are the first signs of emphysema?

The first sign is usually breathlessness during activity, such as climbing stairs, that gradually gets worse. A chronic cough, wheezing and tiring more easily are also common. Many people put early symptoms down to aging or being out of shape.

What is the difference between emphysema and COPD?

Emphysema is a type of COPD. COPD is the umbrella term for chronic lung diseases that block airflow, including emphysema (damaged air sacs) and chronic bronchitis (inflamed airways with mucus). Most people with COPD have elements of both.

Can emphysema be reversed?

No. The damage to the air sacs is permanent. However, stopping smoking slows further damage, and inhalers, pulmonary rehabilitation and oxygen improve breathing and daily function. Valves or surgery help selected people.

What is the life expectancy with emphysema?

It varies widely. People with mild emphysema who stop smoking may live near-normal lifespans. Severe emphysema with low oxygen and frequent flare-ups shortens life expectancy. Doctors use measures such as the BODE index to estimate outlook.

Can nonsmokers get emphysema?

Yes. Alpha-1 antitrypsin deficiency, long-term exposure to secondhand smoke, indoor smoke from cooking fuels, and occupational dusts and fumes can cause emphysema in people who have never smoked.