Chronic obstructive pulmonary disease (COPD) refers to conditions that cause blocked airflow in the lungs. Forms of COPD include emphysema and chronic bronchitis, while symptoms can involve tightness in the chest, wheezing, and coughing. Experts state that smoking is a common cause of COPD, but a genetic form of the disease can occur in some cases.

According to the Centers for Disease Control and Prevention (CDC), about 16 million people in the United States have a diagnosis of COPD. However, experts believe this statistic is higher due to an unknown number of undiagnosed cases.

The article discusses what causes COPD and its associated risk factors, treatments, and prevention.

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Symptoms of COPD may be mild initially and can gradually worsen as the disease progresses. The symptoms may vary by person depending on the underlying cause and severity of the diagnosed COPD.

Common symptoms of COPD include:

  • wheezing
  • shortness of breath
  • chest tightness
  • coughing with or without increased mucus
  • fatigue
  • decreased exercise tolerance
  • depression

In the U.S., cigarette smoking causes up to 90% of COPD cases. Over time, the chemicals in cigarettes can damage the air sacs in the lungs. The small air sacs then lose their elasticity, which impairs the exchange of oxygen and carbon dioxide. This damage in the lungs additionally leads to swelling and inflammation, which impairs breathing.

Although smoking is what commonly causes COPD the majority of the time, a genetic form of the disease can also occur. Alpha-1 antitrypsin (AAT) deficiency is an inherited condition that interferes with the body’s ability to make the protein AAT, which normally resides within the lungs and the bloodstream. It helps protect the lungs from the damage due to inflammation that can lead to emphysema and COPD. People whose bodies do not produce enough of this protein are more likely to develop emphysema at a younger age.

AAT deficiency develops in about 1 in 2,500 people.

The biggest risk factor for developing COPD is smoking. Additional risk factors for COPD may include:

  • breathing in secondhand smoke
  • exposure to environmental toxins, such as chemicals, fumes, and dust
  • continued exposure to air pollution
  • a history of lung infections such as tuberculosis

A doctor can diagnose COPD with a combination of tools. These may include:

  • Medical history and physical exam: Doctors assess medical history, including smoking history, to determine risk factors for COPD. They also perform a physical exam, including listening to lung sounds and identifying known signs of COPD.
  • Chest X-ray: A chest X-ray alone does not detect COPD. However, it helps evaluate other conditions, such as pneumonia and lung cancer.
  • Pulmonary function test: A pulmonary function test includes using spirometry to diagnose COPD. The test evaluates lung function by measuring how well a person can get air in and out of the lungs. Interpreting the spirometry results helps confirm a diagnosis of COPD in addition to the severity of the disease.
  • Arterial blood gas: Doctors may order an arterial blood gas (ABG), which involves taking a blood sample to measure the blood’s carbon dioxide and oxygen levels. Though it does not diagnose COPD, it can provide clues. It assists in providing information on how well gas exchange occurs in the lungs.
  • AAT deficiency screen: This screening involves obtaining a blood sample to identify the presence of an AAT deficiency.

The prognosis for people with COPD varies greatly and often requires the consultation of a doctor.

The stage of COPD a person has, the severity of shortness of breath, and the number of acute flareups that result in hospitalizations can affect projected life expectancy.

A 2020 study looked at life expectancy and loss of life expectancy depending on the stage of COPD. Researchers found that people with severe stage COPD had about 8–9 years of reduced life expectancy in certain cases.

Although there is currently no cure for COPD, treatments are often effective in reducing symptoms, improving quality of life, and slowing the progression of the disease.

Appropriate strategies often depend on the stage of COPD and present symptoms. Treatment usually includes a combination of the interventions below.

Lifestyle changes

Lifestyle changes may play a significant role in the treatment and management of COPD.

Helpful lifestyle changes can include:

  • Quitting smoking: Quitting smoking is essential to help slow down the progression of COPD.
  • Reducing lung irritants: Avoiding air pollution and other lung irritants, such as fumes and chemicals, as much as possible can also help manage symptoms and exacerbation.
  • Exercising regularly: Participating in regular exercise can strengthen the heart and improve cardiovascular function in those with COPD.


Doctors may prescribe various types of medication to treat COPD.

Such medications may include:

  • Bronchodilators: Bronchodilators open up the airway to make breathing easier. They may help reduce wheezing, shortness of breath, and chest tightness.
  • Steroids: Steroids decrease inflammation in the lungs. Doctors can recommend administering these steroids through inhalation, pills, or IV fluids.
  • Antibiotics: Antibiotics can help treat lung infections that may occur in people with COPD.

Oxygen therapy

People diagnosed with COPD may have low blood oxygen levels. Administering supplemental oxygen therapy through a mask or nasal cannula may improve breathlessness.

Pulmonary rehabilitation

Pulmonary rehabilitation therapy provides education and support for people with COPD. The program often involves a series of classes by healthcare professionals — these classes may include information on breathing exercises, proper exercise and nutrition plans, and medication management.

Read more about pulmonary rehabilitation and Medicare coverage.

Bi-level positive airway pressure

Bi-level positive airway pressure (BiPAP), or BPAP, is a form of noninvasive ventilation breathing support for the lungs.

BiPAP uses a machine to deliver pressure to the airway through a mask that an individual wears. The air pressure helps decrease the effort a person needs to breathe, reduces high carbon dioxide levels, and improves oxygen levels. It may help people who have trouble getting carbon dioxide out of their lungs.

The best way to reduce the risk of COPD is to avoid smoking. For people who already smoke, quitting is vital to prevent COPD. Avoiding secondhand smoke from cigarettes, pipes, and cigars also helps prevent these conditions.

Many COPD symptoms, such as coughing, wheezing, and breathlessness, can develop with several other less threatening conditions. However, when respiratory symptoms persist without a known cause, an individual should speak with their doctor.

Diagnosing COPD as soon as possible helps the healthcare team develop a rapid action plan to treat COPD symptoms and help slow the progression of the disease.

COPD, which includes chronic bronchitis and emphysema, involves lung diseases that block airflow in the lungs. The primary cause of COPD is smoking cigarettes. However, in rare cases, a person could have an AAT deficiency, an inherited, genetic form of COPD.

Currently, there is no cure for COPD, and the disease has the potential to progress. Treatments, such as lifestyle changes, medication, and oxygen therapy, can help reduce symptoms and slow disease progression.

Avoiding and quitting smoking is the primary method for preventing COPD.