Chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that makes it hard to breathe. It includes two main conditions: emphysema (destruction of the air sacs) and chronic bronchitis (long-term inflammation and mucus production in the airways). Most people with COPD have a combination of both.

COPD is primarily caused by long-term exposure to irritating gases or particulate matter, most often from cigarette smoke. It develops slowly and is usually diagnosed in middle-aged or older adults. Although the lung damage cannot be fully reversed, treatments can relieve symptoms, reduce the frequency of exacerbations, improve exercise tolerance, and slow progression. Quitting smoking is the single most effective step to prevent worsening of the disease.

Symptoms of COPD often do not appear until significant lung damage has occurred. They typically worsen over time and may include:

• Shortness of breath, especially during physical activities
• Chronic cough that may produce mucus (sputum)
• Frequent respiratory infections
• Wheezing
• Chest tightness
• Unintended weight loss (in later stages)
• Swelling in ankles, feet, or legs
• Fatigue

People with COPD may experience periods of worsening symptoms called exacerbations, often triggered by respiratory infections or air pollution. During an exacerbation, breathing becomes more difficult and may require urgent medical care or hospitalization.

The main cause of COPD in developed countries is tobacco smoking. Long-term exposure to other lung irritants also contributes:

• Secondhand smoke
• Air pollution
• Workplace dusts, chemicals, and fumes
• Indoor air pollution from biomass fuel used for cooking and heating (especially in low-resource settings)

A rare genetic condition, alpha-1 antitrypsin deficiency, can cause COPD even in people who have never smoked. In this disorder the body lacks a protein that protects the lungs from damage. Recurrent severe respiratory infections in childhood may also increase later risk.

Key risk factors include:

• Current or former cigarette smoking (the most important risk factor)
• Long-term exposure to secondhand smoke, air pollution, or occupational dusts and chemicals
• Age — most people are at least 40 when symptoms begin
• Asthma or childhood respiratory infections
• Genetic factors, particularly alpha-1 antitrypsin deficiency
• Lower socioeconomic status (often linked to greater exposure to pollutants and smoking)

COPD can lead to serious complications:

• Respiratory infections (colds, flu, pneumonia) that can trigger dangerous exacerbations
• Heart problems, including heart attack and heart failure
• Lung cancer (smoking is a shared risk factor)
• Pulmonary hypertension (high blood pressure in the lung arteries)
• Depression and anxiety
• Frailty, muscle loss, and reduced ability to perform daily activities

The most important preventive measure is never starting to smoke or quitting if you currently smoke. Other helpful steps:

• Avoid secondhand smoke and air pollutants whenever possible
• Use protective equipment if you work with chemicals, dust, or fumes
• Get vaccinated against influenza, COVID-19, pneumococcal disease, and other recommended vaccines
• If you have alpha-1 antitrypsin deficiency, discuss specific management with a specialist

For people who already have COPD, preventing exacerbations through vaccination, prompt treatment of infections, and adherence to maintenance therapy is critical.

COPD is diagnosed using:

• Spirometry — the essential test. It measures how much air you can exhale and how quickly. A reduced FEV1/FVC ratio that does not fully reverse with bronchodilator confirms airflow obstruction.
• Medical history and physical examination
• Chest X-ray or CT scan to look for emphysema and rule out other conditions
• Arterial blood gas analysis in more advanced disease
• Alpha-1 antitrypsin level testing in selected patients (younger age of onset, family history, or limited smoking history)

Severity is staged according to spirometry results and symptom burden (GOLD classification).

See a healthcare professional if you have chronic cough, shortness of breath, or frequent respiratory infections, especially if you smoke or have smoked in the past. Early diagnosis allows earlier intervention.

Seek emergency care for:

• Severe shortness of breath or inability to speak in full sentences
• Blue or gray lips or fingernails
• Rapid heartbeat
• Confusion or extreme drowsiness
• Symptoms that do not improve with usual medications

Treatment aims to relieve symptoms, improve exercise tolerance, prevent exacerbations, and improve quality of life.

• Smoking cessation — the most important intervention at every stage
• Bronchodilators — short-acting for rescue; long-acting (LABA, LAMA, or combination) for daily maintenance
• Inhaled corticosteroids — often combined with long-acting bronchodilators for patients with frequent exacerbations or asthma features
• Phosphodiesterase-4 inhibitors and other oral medicines in selected cases
• Oxygen therapy — for people with severe resting low oxygen levels
• Pulmonary rehabilitation — structured program of exercise, education, and support that improves function and reduces hospitalizations
• Vaccinations and prompt treatment of infections
• Surgery or procedures — lung-volume reduction, endobronchial valves, or lung transplant in carefully selected advanced cases
• Management of comorbidities (heart disease, osteoporosis, depression, etc.)

Daily self-management is essential:

• Take maintenance inhalers every day as prescribed, even when feeling well
• Learn and practice correct inhaler technique
• Recognize early signs of an exacerbation and follow your action plan
• Stay active within your limits; pulmonary rehabilitation techniques can help
• Eat a nutritious diet and maintain a healthy weight
• Avoid lung irritants (smoke, strong fumes, air pollution)
• Get recommended vaccinations
• Join a support group or seek counseling if depression or anxiety develops

Bring the following information:

• Detailed smoking history (years smoked, packs per day, quit date if applicable)
• Description of symptoms and how they affect daily activities
• List of all medicines and inhalers (bring the devices)
• Record of recent exacerbations or hospitalizations
• Questions about pulmonary rehabilitation, oxygen, inhaler options, and advanced therapies
• Any previous lung-function test results