What Is Emphysema, and What Causes It? (original) (raw)

Emphysema is a form of chronic (long-term) lung disease that causes shortness of breath. Doctors estimate that more than 3 million people in the U.S. have been diagnosed with emphysema. Many more don't know they have it.

Emphysema is one of the two main conditions that make up chronic obstructive pulmonary disease (COPD). The other is chronic bronchitis.

Emphysema vs. bronchitis

Emphysema is caused by the destruction of air sacs in the lungs, mainly from exposure to cigarette smoke. Symptoms include shortness of breath, even when resting, coughing with mucus, wheezing, and tightness in the chest.

Chronic bronchitis is an inflammation in the lining of the bronchial tubes, which carry air to the air sacs of the lungs. Symptoms include a frequent cough with mucus (aka "smoker's cough"), wheezing, and chest pain.

Many people have both diseases at the same time.

Emphysema vs. COPD

Emphysema and chronic bronchitis are the two main types of chronic obstructive pulmonary disease (COPD). These conditions are called "chronic" because they are ongoing (for life) and "obstructive" because it’s as though something is blocking the smooth flow of air in and out of the lungs. "Pulmonary" is a medical term for "lung."

Many diseases fit under the COPD umbrella. They generally have symptoms such as shortness of breath, chest wheezing and tightness, and a cough that produces mucus. Although there is no cure for COPD, there are many options for treating the symptoms. COPD is the third leading cause of death worldwide, according to the World Health Organization.

You get emphysema when the linings of the tiny air sacs (called "alveoli") in your lungs become damaged beyond repair. Over time, your lung damage gets worse. Here’s what happens:

• The fragile tissues between air sacs are destroyed and air pockets form in the lungs.
• Air gets trapped in these pouches of damaged tissue.
• The lungs slowly get larger, and you find it harder to breathe.

If you have symptoms of emphysema, your doctor will order tests to see how well your lungs work. If you have the condition, you won’t be able to empty your lungs of air as quickly as you should. Doctors call this "airflow limitation."

There are three main types of emphysema:

Centriacinar. This is the most common type. It is usually linked to cigarette smoking and occurs mainly in the upper half of the lungs.

Panacinar. This usually occurs in the lower half of the lungs. It's not linked to smoking but rather a rare genetic disease called homozygous alpha-1 antitrypsin deficiency.

Paraseptal. This usually affects the outer areas of the lungs, like the septa or pleura. People who get this type of emphysema usually have one of the other types as well.

There are two major causes of emphysema:

Smoking. Studies show that smokers are about six times more likely to develop emphysema than nonsmokers. Cigarettes are the main culprit, though marijuana and cigar smoke can also hurt your lungs. Smoking damages lung tissue, irritates your airways, and destroys your cilia (cells in your lungs that move debris and germs from your airways). When your cilia are destroyed, you can't clear your airways and you produce mucus. All of this leads to shortness of breath.

Doctors don’t know why some smokers get emphysema and others don’t.

There's no cure for emphysema, but if you’re a smoker with the disease, kicking the habit might slow down the damage it does to your lungs.

AAT deficiency. Alpha-1 antitrypsin (AAT) is a natural protein that circulates in human blood. Its main function is to keep white blood cells from damaging normal tissues. The body needs these cells to fight infections.

An estimated 100,000 people in the U.S. are born with a condition that keeps their bodies from making enough AAT. If you have AAT deficiency, your normal white blood cells will damage your lungs. The harm is even worse if you smoke.

Over time, most people with severe AAT deficiency develop emphysema. If you have this disease, you may also develop liver problems.

Other possible causes

Secondhand smoke. Doctors have long known that being around cigarette smoke -- even if you aren’t a smoker -- can lead to lung damage over time. Several studies suggest that people exposed to high amounts of secondhand smoke have higher odds of getting emphysema.

Air pollution. Scientists believe this plays a role, but it’s hard to measure. That’s because most people are exposed to pollution regularly, but emphysema takes years to develop.

People often have emphysema for years before they get diagnosed with it. This is because the symptoms take time to show up and can be mistaken for common age-related problems. Typical symptoms include:

• Shortness of breath
• Persistent cough, with or without mucus
• Wheezing
• Tightness in your chest

As the disease progresses, you might find you are short of breath even when not doing anything physical. You might also lose weight and have fatigue just from the sheer effort of breathing.

Emphysema stages

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) labels COPD in four categories. Although not everyone with COPD has emphysema, doctors use these four stages to categorize emphysema:

• Stage I: Mild emphysema. Your lungs operate at 80% or more of the capacity of a healthy person of the same age, sex, and height.
• Stage II: Moderate emphysema. Your lung capacity is 50%-79% of the capacity of a healthy person.
• Stage III: Severe emphysema. Your lung capacity is 49%-30% of the capacity of a healthy person.
• Stage IV: Very severe. Your lung capacity is less than 30% of the capacity of a healthy person.

Your doctor will talk to you about your health and any recent changes or problems you might have noticed. They often run a variety of tests before diagnosing emphysema. The tests may include:

Physical exam

Your doctor will check your weight and blood pressure. They’ll listen to your heartbeat and lungs and keep an eye out for anything that seems strange or unusual.

If you have advanced emphysema, your doctor may notice any of the following:

• You have a "barrel chest" caused by larger-than-normal lungs.
• You’re wheezing and having a hard time getting air out of your lungs.
• Your fingertips are rounded. Doctors call this “clubbing.”
• You purse your lips when you breathe, like you’re blowing a kiss.
• The oxygen levels in your blood are low (hypoxemia).
• The carbon dioxide levels in your blood are high (hypercarbia) because emphysema makes it hard to exhale properly.
• Your lips have a blue tinge (cyanosis), another sign of low oxygen in your blood.

Malnutrition causes muscles to slowly waste away in advanced emphysema.

Pulmonary function tests (PFTs)

For this exam, you may sit inside an enclosed booth and breathe into a tube. This will allow your doctor to measure:

• How much air your lungs can hold
• How fast you can blow air out of your lungs
• How much air stays trapped in your lungs after you exhale
• Whether you’re able to breathe better after using medicines you inhale, such as albuterol

If you have normal lungs, you’ll likely be able to empty most of the air from them in 1 second. If you have emphysema, it’ll probably take longer.

Chest X-ray and CT scan

If you have advanced emphysema, your lungs will appear to be much larger than they should be. In the early stages of the disease, your chest X-ray may look normal. Your doctor can’t diagnose emphysema with an X-ray alone.

A CT scan of your chest will show if the air sacs (alveoli) in your lungs have been destroyed. These make it hard for you to breathe out normally.

Complete blood count

This simple blood test usually shows normal amounts of white and red blood cells. In advanced emphysema, your body produces more red blood cells to make up for decreased oxygen. These cells carry oxygen.

If your white blood cell count is higher than normal, that’s a possible sign of infection.

Emphysema can’t be cured, but many treatments can ease symptoms by making it easier for you to breathe. These can also prevent other problems and keep the disease from getting worse.

If you smoke, one of the most important treatments is to stop smoking.

Other treatments include:

Bronchodilators

These drugs relieve symptoms by relaxing the muscles in your lungs and making your air passages wider. Bronchodilators often use an inhaler ("puffer"). They also come in pill or liquid form, but these don’t work as well as an inhaler and can have more side effects.

There are short-acting and long-acting bronchodilators. The short-acting drugs work faster but don’t last as long. The long-acting ones don’t work as fast, but they last longer. If your emphysema symptoms are mild, your doctor may recommend you take short-acting bronchodilators during flare-ups. As your symptoms get worse, you may have to take daily doses of long-acting bronchodilators.

Bronchodilators come in two forms:

• Anticholinergics stop the muscles around your airways from tightening. They also make it easier to clear mucus from the lungs.
• Beta-agonists relax muscles around the airways.

Your doctor may prescribe short-acting beta-agonists only when you need them to control your symptoms. They start working within 3 to 5 minutes and last 4 to 6 hours. But they may cause your heart to race. They can also cause shakiness and cramping in the hands, legs, and feet. These side effects can make you feel anxious. That, in turn, can make it harder for you to breathe.

Short-acting anticholinergics start working in about 15 minutes and last 6 to 8 hours. Long-acting forms of these drugs can take about 20 minutes to work and last up to 24 hours. The most common side effects of these drugs are dry mouth and difficulty peeing.

If you have advanced emphysema, your doctor may prescribe a long-acting inhaled bronchodilator. They’re used on a regular schedule to open your airways and keep them open.

PDE4 inhibitors

Oral drugs called phosphodiesterase-4 (PDE4) inhibitors have proved helpful in treating COPD.

Several clinical trials showed the PDE4 drug roflumilast improved lung function when used with bronchodilator therapy. Some studies found it also led to fewer flare-ups.

The FDA has approved roflumilast for bronchitis, not emphysema, but the two conditions often have similar symptoms.

Steroids and combination medicines

Steroids reduce swelling and mucus in your airways so you can breathe easier. Usually, you breathe them in with an inhaler.

Over time, steroids can have serious side effects, including weight gain, diabetes, cataracts, high blood pressure, weakened bones, and an increased risk of infection.

Your doctor may recommend that you use a steroid combined with a beta-agonist or an anticholinergic bronchodilator, or with both types of bronchodilators, in a single inhaler. This provides more benefits than any of these drugs alone.

Mucolytics

These drugs help thin the mucus in your lungs so you can cough it up more easily. Studies show using mucolytics can reduce flare-ups, especially if your emphysema is more severe.

Protein therapy

Some people have an inherited form of emphysema that’s caused by a lack of AAT. Getting infusions of AAT can help slow down lung damage.

Oxygen therapy

As your emphysema progresses, you may need extra oxygen to help you breathe. Your doctor will prescribe how much oxygen you need and when you should be taking it. You can take supplemental oxygen in one of the following three ways:

1. Oxygen concentrator. This device removes other gases from the air and gives you near-pure oxygen. (Air normally contains 21% oxygen.)
2. Liquid system. This is supercooled, pure oxygen stored in a canister that looks like a thermos.
3. Oxygen cylinders. These contain 100% oxygen, stored under high pressure in large or small tank-like containers.

Vaccines

The flu vaccine doesn’t treat emphysema directly, but doctors recommend you get one every year. They also suggest you get a pneumonia shot every 5 to 7 years to prevent infection. If you have emphysema, you have higher odds of getting serious problems from flu and pneumonia. You should also get a COVID-19 vaccine.

Surgery

Operations for more serious cases of emphysema include:

Lung volume reduction surgery (LVRS). In this procedure, a surgeon removes part of one or both of your lungs. The goal is to take out your nonworking air sacs to make it easier to breathe. This is major surgery, so your heart has to be strong and the rest of your lungs need to be healthy before you can have it. You’ll also need to quit smoking and complete a pulmonary rehabilitation program before the operation.

Bullectomy. In rare cases, air sacs in the lungs caused by emphysema grow larger and can press against healthy parts of the lung. These oversized sacs are called bullae. A bullectomy is surgery to remove them.

Lung transplant. Lung transplants are possible for the most severe cases. This is a 6- to 10-hour surgery, after which you’ll be in the hospital for 8 to 21 days -- if there are no complications. The two biggest risks of the operation are infection and rejection of the transplanted organ.

If you have emphysema, you are at a higher risk of getting very sick from respiratory infections. So, COVID can be a big concern, just as influenza is. You are more likely than others to have severe breathing problems, develop complications, and need to be hospitalized if you get COVID.

Your risk is higher because emphysema already has damaged your lungs. Also, when you have emphysema, your immune system doesn't work as well, which may make it harder for you to fight off infections. It's not clear that people with emphysema and other forms of COPD actually get COVID more often. It's possible that they are infected at lower rates because they do more to protect themselves than many people do.

Here's what you can do to lower your risks:

• Stay up to date with COVID vaccines.
• Avoid people who are sick, especially those with a cough, fever, or other possible symptoms of COVID or any other respiratory illness.
• Practice social distancing — keep 6 feet away from others when you can.
• Wear a mask in public.
• Wash your hands frequently.
• Avoid touching your nose, mouth, and eyes.

Can COVID cause emphysema?

Doctors have found just a few cases in which people who seemed to have healthy lungs developed emphysema as a complication of COVID.

The most important thing you can do to prevent emphysema is not smoking. If you smoke now and are ready to quit, talk to your doctor and make a plan.

Other things you can do:

• Avoid secondhand smoke.
• Avoid air pollution, chemical fumes, dust, pollen, and pet dander.
• Wear a mask if you work with chemical fumes or dust.

When you have emphysema, tiny air sacs in your lungs are damaged. That makes it hard to breathe. Smoking is the most common cause. You can't cure emphysema, but treatment can help you feel better.

What is the life expectancy of someone with emphysema?

The outlook varies greatly, depending in part on your smoking history and how advanced your emphysema is. A smoker who quits and has mild emphysema can have a normal lifespan. A never-smoker with moderate to advanced emphysema might lose over a year of expected lifespan. But a smoker who has severe emphysema and keeps smoking might die 10 years earlier than expected.

Can emphysema affect only one lung?

Yes, it's possible to have emphysema in one lung. This can happen with a type called bullous emphysema, which causes large air pockets in one or both lungs. While this type of emphysema is most commonly caused by smoking, it also can be caused by several genetic conditions.

How long does subcutaneous emphysema last?

Subcutaneous emphysema is a condition in which air gets trapped under the skin. It's not the same as emphysema in your lungs. It's often a result of surgery or traumatic injuries that release air from the lungs or other organs into surrounding areas, or an infection that creates trapped gases. How long it lasts depends on the cause and treatment. But it's not typically a long-lasting or fatal condition.