Which statement best describes airway changes in chronic bronchitis?

• A. Decreased mucus gland size
• B. Destruction of alveolar walls
• C. Hypersecretion due to mucous gland hypertrophy
• D. Reduced inflammatory cells

Answer: (C)

Chronic bronchitis mainly features mucus hypersecretion driven by mucous gland hypertrophy (and goblet cell hyperplasia). This increases the amount and thickness of mucus in the airways, producing the productive cough that characterizes the condition. The Reid index, which measures the thickness of the mucous gland layer relative to the airway wall, is increased in chronic bronchitis, reflecting this hypertrophy. Destruction of alveolar walls is more typical of emphysema, not chronic bronchitis, and the disease generally involves increased inflammatory cells rather than reduced. So the description of hypersecretion due to mucous gland hypertrophy best captures the airway changes.