COPD

If healthy lungs are like fresh, springy sponges that empty easily, COPD lungs are like sponges that have lost their snap and whose passages are clogged and narrowed. Air gets in but struggles to come out, so people feel persistently short of breath — at first only on exertion, later even at rest — usually after years of smoking.

COPD, chronic obstructive pulmonary disease, is a common, treatable condition defined by persistent, largely irreversible airflow limitation due to airway and alveolar abnormalities from long-term exposure to harmful particles or gases. It blends two overlapping processes: emphysema (destruction of alveolar walls and elastic recoil) and chronic bronchitis (inflamed, mucus-producing airways). Spirometry confirms it by showing a reduced FEV1/FVC ratio that does not fully reverse with a bronchodilator.

The leading cause is cigarette smoking, though biomass smoke, occupational dust, air pollution, and alpha-1 antitrypsin deficiency also contribute. COPD is progressive but its trajectory can be improved: stopping smoking, inhaled therapy, vaccination, and pulmonary rehabilitation slow decline and ease symptoms. Unlike asthma, the obstruction is mostly fixed, though some reversibility and overlap with asthma can occur.