What are the risk factors for spontaneous pneumothorax (collapsed lung)?

From the Guidelines

Spontaneous pneumothorax is strongly associated with underlying lung disease, smoking, and genetic disorders.

Risk Factors

• Genetic disorders: Familial pneumothorax, Birt-Hogg-Dubé syndrome, tuberous sclerosis complex, lymphangioleiomyomatosis, and connective tissue disorders such as Marfan syndrome and Ehlers-Danlos syndrome are associated with an increased risk of spontaneous pneumothorax 1.
• Cystic fibrosis: Patients with cystic fibrosis are at a higher risk of developing spontaneous pneumothorax, with a reported incidence of 0.64% per annum and 3.4% overall 1.
• Smoking: Smoking is a significant risk factor for primary spontaneous pneumothorax, with a lifetime risk of 12% in healthy smoking men compared to 0.1% in non-smoking men 1.
• Underlying lung disease: Secondary pneumothorax is associated with underlying lung disease, such as pulmonary tuberculosis 1.

Demographics

• Sex: The incidence of spontaneous pneumothorax is higher in men than in women, with a reported incidence of 18-28/100,000 per year for men and 1.2-6/100,000 per year for women 1.
• Age: The risk of spontaneous pneumothorax increases with age, particularly in patients with cystic fibrosis 1.

From the Research

Risk Factors for Spontaneous Pneumothorax

The risk factors for spontaneous pneumothorax can be categorized into several groups, including:

• Demographic factors:
  • Male gender 2
  • Younger age 2
• Physical characteristics:
  • Greater height 2
  • Lower body mass index (BMI) 2
  • Greater height growth per year 2
  • Pectus excavatum (PE) deformities in the chest wall 3
• Lifestyle factors:
  • Tobacco smoking 4
  • Use of cannabis (although no association was found in one study) 5
• Medical conditions:
  • Chronic obstructive pulmonary disease (COPD) 4
  • Underlying interstitial lung disease 6

Secondary Spontaneous Pneumothorax

Secondary spontaneous pneumothorax can be a life-threatening condition, and the risk factors for this condition include:

• Underlying lung disease 6
• Medical comorbidities 6
• Prolonged air leakage, which can increase morbidity and mortality in thoracic surgery 6

Primary Spontaneous Pneumothorax

Primary spontaneous pneumothorax (PSP) has been found to have several risk factors, including:

• Tobacco smoking 4
• Male gender 2
• Younger age 2
• Greater height 2
• Lower BMI 2
• Greater height growth per year 2
• Pectus excavatum (PE) deformities in the chest wall 3