Chronic Obstructive Pulmonary Disease (COPD)

• Very prevalent worldwide
  • 1.5 million Canadians affected
  • 4th leading cause of death

Two clinical entities comprise COPD:

• often overlap

1. emphysema

• abnormal permanent enlargement of airways distal to terminal bronchioles with destruction of their walls

2. chronic bronchitis

• productive cough for more than 3 months in 2 consecutive years (in the absence of an alternative diagnosis)

Causes:

• smoking remains most important cause (85-90%)
  • only 10-15% of smokers develop COPD
• genetic factors (?1-antitrypsin deficiency)
• passive smoke (household contacts, occupational exposure)
• environmental factors (air pollution)

Complications:

• dyspnea, fatigue, limitations of activities
• frequent flares or “exacerbations”
  • worsening of symptoms
  • precipitated by a variety of stressors:
    • infection, changes in weather, humidity, ozone, etc.
  • often debilitating
    • may take weeks to months to return to baseline function
    • may never return to baseline function
• pulmonary hypertension and cor pulmonale
  • chronic hypoxia, destruction of pulmonary capillaries
    

Treatment:

• stop smoking!
• medications
  • oxygen if necessary
  • medications
    • steroids (decrease inflammation)
    • beta-agonists e.g. salbutamol (bronchodilator)
    • anticholinergics e.g. ipratropium (bronchodilator, decrease secretions)
    • antibiotics for infectious exacerbations
      

   

Prognosis

• median survival is approximately 4 years in severe COPD