Emphysema is a type of lung disease that destroys lung tissue and reduces lung function. Doctors classify the disease in stages according to its severity. Stage 4 emphysema is the most severe stage, in which a person’s symptoms may significantly affect their quality of life.

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Although there is no cure for emphysema, treatments are available to help manage the symptoms and slow the progression of the disease.

By the time a person reaches stage 4 emphysema, treatment focuses on easing symptoms and boosting blood oxygen levels to prevent further complications.

This article describes what stage 4 emphysema is, including its signs and symptoms. We also provide information on diagnosing, treating, and managing the condition.

Finally, we outline the life expectancy for people living with the condition and offer advice on when to see a doctor.

Emphysema belongs to a group of lung diseases that doctors refer to as chronic obstructive pulmonary disease (COPD).

Emphysema involves damage to the tiny air sacs, or alveoli, within the lungs. Over time, the inner walls of the alveoli rupture, creating large, air-filled pockets within the lungs. Doctors refer to these enlarged air pockets as “bullae.”

As the lungs lose functioning tissue, they become less effective at exchanging oxygen and carbon dioxide. This results in respiratory issues and low blood oxygen levels, which may cause fatigue and an overall reduction in quality of life.

Medical professionals may use a staging system to determine the severity of emphysema. This system uses a person’s forced expiratory volume (FEV) score to determine disease severity. The FEV1 score is a measurement of how much air a person can force out of their lungs in 1 second.

Stage 4 emphysema is the most severe stage of the disease, in which a person produces an FEV1 score that is below 30% of the expected value.

However, most medical professionals now consider the staging system obsolete, with doctors preferring to use the global initiative for chronic obstructive lung disease (GOLD) severity assessment. This assessment uses the FEV1 score along with additional tests to determine disease severity.

The table below shows the stages and corresponding GOLD grades of COPD, along with information on the FEV1 score:

StagesGOLD gradeCOPD or emphysema severityFEV1 score
IGOLD 1Mild: A person may not be aware that their lungs are not functioning optimally.Greater than or equal to 80% of the predicted value.
2GOLD 2Moderate: A person begins to notice symptoms and seeks medical attention.Between 50% and 79% of the predicted value.
3GOLD 3Severe: A person may find exercising challenging and experience shortness of breath.Between 30% and 49% of the predicted value.
4GOLD 4Very severe: At this stage, the condition is life-threatening and affects quality of life.Below 30% of the predicted value.

Emphysema is a progressive disease, meaning it worsens over time. Stage 4 is the final stage and presents with the most serious symptoms. These symptoms can affect a person’s physical and mental health and significantly impact the quality of life.

Physical health symptoms

Physical signs and symptoms of emphysema may include:

Mental health symptoms

Mental symptoms of emphysema may include:

Signs that emphysema is affecting quality of life

A person with severe emphysema may experience a reduction in their quality of life. Possible changes include:

Doctors use a range of tests to diagnose advanced emphysema. We outline these below.

Laboratory tests

A doctor may order the following tests to confirm emphysema:

Complete pulmonary function tests (PFTs)

PFTs are noninvasive tests that indicate how well the lungs are working, according to the following parameters:

  • lung capacity
  • airflow rate
  • gas exchange

Spirometry is a type of PFT that measures how quickly and easily a person can breathe air into and out of their lungs. Additional PFTs include bronchodilator reversibility testing and carbon monoxide diffusion capacity (DLCO).

Arterial blood gas test

Emphysema reduces the lungs’ ability to transport oxygen into the blood. This causes a rise in carbon dioxide levels in the blood, which makes it more acidic.

An arterial blood gas test measures blood oxygen and carbon dioxide levels, as well as arterial blood acidity.

Images

A doctor may order the following diagnostic imaging tests to confirm advanced emphysema:

  • CT scan: This imaging technique is most effective at identifying general signs of emphysema. Specialized CT scans can also identify certain forms of lung damage and whether certain treatment options will be effective.
  • X-ray: This imaging technique can show lung hyperinflation and a flattened diaphragm, which are symptoms of advanced emphysema.
  • Echocardiogram: This form of ultrasound can help doctors identify secondary pulmonary hypertension, which can occur due to COPD.

Walking test

A 6-minute walking test is a measure of a person’s aerobic exercise capacity. During the test, a person walks at their usual pace for 6 minutes while a doctor measures their blood pressure, pulse, and oxygen level.

The test can help determine if a person with emphysema requires long-term oxygen therapy (LTOT).

Other assessments

To further understand the severity of emphysema, a doctor will ask a person to answer COPD questionnaires, including the COPD Assessment TEST (CAT) and the COPD Control Questionnaire (The CCQ).

In the CAT questionnaire, people answer questions on a scale from 0–5, according to symptom severity. The higher the total score at the end of the test, the more severe the symptoms.

Another test for assessing how well the lungs are functioning is cardiopulmonary exercise testing. Doctors will check how the lungs and heart function before and during mild exercise.

There is no cure for emphysema. Instead, treatment focuses on managing the symptoms and slowing the progression of the disease. Since stage 4 emphysema is the last stage of the disease, treatment focuses on managing the symptoms and preventing complications.

Doctors may treat stage 4 emphysema with medication, oxygen therapy, surgery, or a combination.

Medication

Doctors may prescribe medications to help with the following:

  • relaxing and widening the airways
  • reducing inflammation of the airways
  • reducing the production of mucus

A doctor may prescribe one or more of the following medications:

People may also receive antibiotics to treat recurrent chest infections and vaccines to protect them from flu and pneumonia. Doctors may also consider biologic injections for people who have both COPD and asthma.

Learn more about the above and additional medications for COPD here.

Oxygen therapy

A person who experiences complications due to low blood oxygen levels may require oxygen therapy to prevent levels from becoming dangerously low.

A person will typically receive the oxygen through nasal tubes or a face mask connected to an oxygen tank. Some tanks are portable, meaning a person can use them while away from home.

Surgery

In some cases, a person with severe emphysema may receive lung volume reduction surgery or a lung transplant. Surgery is more common in bullous emphysema, in which there are exceptionally large air pockets within the lungs.

If a person has advanced emphysema, they should strongly consider quitting smoking or vaping. This will have the greatest impact on lung health.

Additional actions a person should take include:

  • Avoiding air pollutants: People should avoid air pollutants, such as secondhand smoke and chemical fumes.
  • Undergoing pulmonary rehabilitation: These personalized programs include exercises to help improve breathing and conserve energy.
  • Taking medication consistently: This is particularly important for people who frequently cough and wheeze.
  • Avoiding lung infections: Where medically appropriate, people with emphysema should receive vaccines to protect against pneumonia and flu.
  • Using supplemental oxygen: A person who finds breathing or daily functioning particularly challenging may require an oxygen tank to help top up their blood oxygen levels.

A person who receives a diagnosis of stage 4 emphysema can live for a decade or more following the diagnosis. The outlook is typically better for those who quit smoking and manage their symptoms well with medication.

Anyone who has emphysema should speak with a doctor if they experience the following:

Stage 4 emphysema is the final and most severe stage of the disease, in which a person may experience low blood oxygen levels due to advanced lung damage. Low blood oxygen levels can lead to chronic fatigue and an overall reduction in quality of life.

Doctors treat advanced emphysema with medications to help relax and widen the airways. Some people may benefit from oxygen therapy to help maintain adequate blood oxygen levels.

If a person’s health continues to deteriorate, doctors may recommend surgery to help improve lung function.

People who receive a diagnosis of stage 4 emphysema typically live for at least a decade following their diagnosis, especially if they quit smoking and manage their symptoms well. It is important that people notify their doctor of any changes to their symptoms so that the doctor can adjust the treatment plan accordingly.