Which of the following is a risk factor for spontaneous pneumothorax?

Which of the following is a risk factor for spontaneous pneumothorax?

• A. Smoking
• B. Regular exercise
• C. Vegetarian diet
• D. Daily aspirin

Answer: (A)

Smoking increases the risk of spontaneous pneumothorax because it damages lung tissue and promotes the formation and rupture of subpleural blebs, especially at the lung apices. When these blebs rupture, air leaks into the pleural space, collapsing the lung. This is a key factor in primary spontaneous pneumothorax, where there is no underlying lung disease, and smoking is the strongest modifiable risk factor, also heightening the chance of recurrence after the first event. Regular exercise, vegetarian diet, and daily aspirin do not have a known mechanistic link to spontaneous pneumothorax. Regular exercise is generally not a risk factor for bleb formation or rupture, and the other options don’t influence the pleural integrity or bleb development in a clinically meaningful way.

Smoking increases the risk of spontaneous pneumothorax because it damages lung tissue and promotes the formation and rupture of subpleural blebs, especially at the lung apices. When these blebs rupture, air leaks into the pleural space, collapsing the lung. This is a key factor in primary spontaneous pneumothorax, where there is no underlying lung disease, and smoking is the strongest modifiable risk factor, also heightening the chance of recurrence after the first event.

Regular exercise, vegetarian diet, and daily aspirin do not have a known mechanistic link to spontaneous pneumothorax. Regular exercise is generally not a risk factor for bleb formation or rupture, and the other options don’t influence the pleural integrity or bleb development in a clinically meaningful way.