Chronic obstructive pulmonary disease

Overview

Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease characterized by long-term breathing problems and poor airflow. The main symptoms include shortness of breath and cough with sputum production. COPD is a progressive disease, meaning it typically worsens over time. Eventually, everyday activities such as walking or getting dressed become difficult.

A close-up view of a healthy lung and a lung affected by COPD

Causes

Long-term exposure to irritating gases or particulate matter, most often from cigarette smoke, is the primary cause of COPD. People with COPD are often at increased risk of heart disease, lung cancer, and a variety of other conditions. Emphysema and chronic bronchitis are the two most common conditions that contribute to COPD. These two conditions usually occur together and can vary in severity among individuals with COPD.

Pathophysiology

Chronic bronchitis and emphysema are the two main conditions that make up COPD. Chronic bronchitis is defined as a chronic cough that produces sputum for three months each year for two years. Emphysema is defined as the destruction of the lungs over time. Most people with COPD have a combination of both conditions.

Diagnosis

COPD should be considered in any patient who has dyspnea, chronic cough, or sputum production. Spirometry is the most reliable method for making the diagnosis. In people with typical symptoms, a post-bronchodilator FEV1/FVC < 0.70 confirms the presence of airflow limitation that is not fully reversible, and thus COPD.

Management

While COPD is a chronic, progressive disease, with the right management, most people with COPD can achieve good symptom control and quality of life, as well as reduced risk of other associated conditions.

Prognosis

The course of COPD is often unpredictable as it can change suddenly, triggered by even small infections such as the common cold. The rate at which it worsens varies between individuals and is not clearly understood.

Epidemiology

COPD affects approximately 329 million people globally (nearly 5% of the population) and resulted in 3.1 million deaths in 2015 (5% of deaths globally).