Chronic Obstructive Pulmonary Disease (COPD)

COPD is a progressive (i.e. gets worse with time), chronic, inflammatory lung disease obstructing air-flow to the lungs, mainly caused by breathing pollutants.

To help understand what is going on with COPD, first please see  brief description of how the lungs work:

The lungs 101

Causes of COPD

COPD damage reduces the natural elasticity of the alveoli (air sacs) and bronchial tubes.   Elasticity is required to force out air/carbon dioxide for exhalation. As a  consequence, unexpelled air is trapped in the lungs, which makes it difficult for the air sacs to deflate and bring in new air

Image: www.lung.net/copd

COPD describes several progressive lung diseases characterized by shortness of breath.  Includes:

•   CHRONIC bronchitis.   The constant irritation/inflammation of the MUCUS MEMBRANE LINING (epithelium) of the bronchial airways (bronchi/bronchioles, which carry air to and from the alveoli of the lungs), causes it to swell and produce mucus, which narrows the airways, making it harder to breathe; a cough ensues to try and clear the mucus.

FYI - Mucus membranes also line the sinuses, GI and urinary tracts

•   Emphysema.   Breakdown of the elastin of lung connective tissues weakens/damages the thin walls and fibers of the alveoli (air sacs) at the end of the smallest bronchial airways (bronchioles); the alveoli walls eventually break down, producing less, but larger air spaces instead of many small ones, and so reducing the surface area available for gas exchange; 

•   Non-reversible asthma

•   Some forms of bronchietasis

COPD Symptoms

COPD is the THIRD leading cause of death in the U.S. affecting ~30 million Americans.   Of those, >50% are unaware they have it

COPD progression causes loss of lung function.     Can increase risk for:

•   Respiratory infections.    E.g. flu, colds, pneumonia - making it even more difficult to breathe

•   Lung cancer 

•   Pulmonary hypertension.    High blood pressure in arteries delivering blood to lung 

•   Heart disease.    Reason not well understood

Diagnosis

A breathing test, called spirometry, measures the amount of air blown out of the lungs in how long.    This simple test can detect COPD ahead of symptoms