COPD (Chronic Obstructive Pulmonary Disease)

What happens in COPD

Normally, the airways branch into smaller tubes ending in tiny air sacs (alveoli), where oxygen passes into the blood. In COPD:

• Chronic bronchitis: the airway lining is inflamed and thickened and produces excess mucus, narrowing the tubes.
• Emphysema: the walls of the air sacs are destroyed, creating larger, less efficient spaces. The lungs lose their elastic recoil, so small airways collapse when you breathe out. See emphysema.

Most people have a mix of both. Air becomes trapped in the lungs, which become overinflated. This makes breathing harder work, especially during activity.

Symptoms

• Breathlessness: first with exertion, such as climbing stairs or hurrying, later with everyday tasks. It usually worsens gradually over years.
• Chronic cough: often the first symptom, frequently dismissed as a "smoker's cough."
• Phlegm (sputum): especially in the morning.
• Wheezing and chest tightness.
• Frequent chest infections, particularly in winter.
• Tiredness and reduced exercise capacity.
• Advanced disease: weight loss, muscle wasting, ankle swelling and morning headaches.

COPD flare-ups (exacerbations)

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

Causes and risk factors

• Smoking: the leading cause in the US. Risk rises with pack-years. Cannabis smoking and vaping also harm the lungs.
• Secondhand smoke.
• Indoor air pollution: burning wood, coal or biomass for cooking and heating, a major cause worldwide.
• Outdoor air pollution.
• Workplace exposures: dusts, chemicals and fumes in mining, construction, farming and manufacturing.
• Alpha-1 antitrypsin deficiency: an inherited condition that causes emphysema at a young age, even in nonsmokers. Everyone with COPD should be tested once.
• Early-life factors: premature birth, childhood chest infections and poor lung growth.
• Long-standing poorly controlled asthma.

Diagnosis

• Spirometry: you blow out as hard and fast as you can into a device. COPD is confirmed when the ratio of air blown out in the first second (FEV1) to the total amount (FVC) is less than 0.70 after a bronchodilator.
• Chest X-ray or CT scan: to look for emphysema, other lung diseases and lung cancer.
• Blood tests: alpha-1 antitrypsin level, blood count (anemia or high red cell counts), and blood eosinophils, which help guide inhaled steroid use.
• Pulse oximetry and arterial blood gases in more severe disease.
• Lung cancer screening with low-dose CT for eligible current and former smokers.

COPD stages (GOLD grades)

Spirometry grades airflow limitation by FEV1 as a percentage of the predicted value:

Treatment decisions also depend on symptom burden and the number of flare-ups in the past year, grouped as A, B and E in current GOLD guidance.

COPD vs asthma

Some people have features of both.

Treatment

Stop smoking

Quitting is the single most effective way to slow COPD at any stage. Nicotine replacement, varenicline and behavioral support greatly improve success. Call 1-800-QUIT-NOW (US) for free help.

Inhalers

• Short-acting bronchodilators (albuterol or ipratropium) for quick relief.
• Long-acting bronchodilators: LAMAs (such as tiotropium) and LABAs (such as salmeterol or formoterol), often combined in one inhaler, for daily maintenance.
• Inhaled corticosteroids added for people with frequent flare-ups and higher blood eosinophil counts.
• Correct inhaler technique is essential. Ask a nurse or pharmacist to check yours.

Pulmonary rehabilitation

A supervised program of exercise, breathing techniques and education, usually 6 to 12 weeks. It improves breathlessness, exercise capacity and quality of life, and reduces hospital admissions. It is one of the most effective treatments for COPD.

Vaccines

Flu (yearly), COVID-19, pneumococcal, RSV for adults aged 75 and over or 50 to 74 at higher risk (per current US guidance), and Tdap.

Other treatments

• Roflumilast or long-term azithromycin for some people with frequent flare-ups.
• Biologic therapy (such as dupilumab) for selected people with high eosinophils and frequent flare-ups.
• Long-term oxygen therapy for people with persistently low blood oxygen. It improves survival in those people.
• Home noninvasive ventilation for some people with high carbon dioxide levels.
• Lung volume reduction (surgery or valves) or lung transplant for selected people with severe emphysema.

Treating flare-ups

Increased bronchodilator use, a short course of oral steroids, and antibiotics when infection is likely. Severe flare-ups need hospital care, oxygen and sometimes breathing support.

Complications

• Frequent chest infections and pneumonia
• Cor pulmonale: right-sided heart failure from lung disease
• Respiratory failure
• Collapsed lung (pneumothorax)
• Lung cancer, which is more common in people with COPD
• Weight loss, muscle weakness and osteoporosis
• Anxiety and depression

Outlook and living with COPD

COPD is progressive, but how fast it advances varies widely. Many people with mild to moderate COPD live for many years with good quality of life, especially if they stop smoking. Outlook is worse with severe airflow obstruction, frequent flare-ups, low body weight and continued smoking. Staying active, eating well, using medicines correctly, getting vaccinated and having an action plan for flare-ups all help. Palliative care can support people with advanced disease to control breathlessness and plan ahead.

Frequently asked questions

What are the first signs of COPD?

Early signs are often a persistent cough with phlegm, particularly in the morning, breathlessness when climbing stairs or hurrying, wheezing, and chest infections that take longer to clear. Because symptoms develop slowly, many people blame age or fitness. Anyone over 35 with these symptoms and a smoking history should ask for spirometry.

What are the stages of COPD?

GOLD grades COPD from 1 to 4 by spirometry: mild (FEV1 80 percent or more of predicted), moderate (50 to 79 percent), severe (30 to 49 percent) and very severe (under 30 percent). Doctors also consider symptoms and flare-up history when choosing treatment.

Can COPD be reversed?

No. The lung damage in COPD is largely permanent. However, stopping smoking slows the decline in lung function to nearly that of a nonsmoker, and inhalers, pulmonary rehabilitation and vaccines improve symptoms, reduce flare-ups and help people stay active.

What is the life expectancy with COPD?

It varies widely. People with mild COPD who stop smoking may have a near-normal life expectancy. Severe COPD with frequent flare-ups, low oxygen levels or low body weight shortens life expectancy. Stopping smoking, pulmonary rehabilitation and, when needed, long-term oxygen improve survival.

Is emphysema the same as COPD?

Emphysema is one type of COPD. It describes destruction of the air sacs. Chronic bronchitis, the other main type, describes inflamed airways with long-term cough and phlegm. Most people with COPD have features of both.