In what ways are asthma and COPD similar?
Impaired pulmonary airflow
Increasing flow resistance
Feeling of breathlessness
What is the presenting symptom of COPD?
Persistent chesty cough
What causes mucous buildup in COPD patients?
What is a major impact of mucous buildup for COPD patients?
Increased frequency of chest infections
What is the most common cause of death in those with COPD?
Pneumonia
How does wheezing in patients with COPD differ from those with asthma?
Wheezing in COPD is persistent
Wheezing with asthma - episodic
What causes persistent wheezing?
What does an Alpha-1-antitrypsin deficiency cause?
What is the function of Alpha-1-antitrypsin?
How does it work?
Protein protecting the lungs from inflammation and disease
Protease inhibitor - inactivates neutrophil elastase; enzyme that breaks down lung tissue
In what sorts of patients is COPD most prevalent?
In what two ways are asthma and COPD the most similar?
What are the main differences between COPD and asthma?
COPD - increasing breathlessness
Asthma - episodic breathlessness
COPD - symptoms will get worse
Asthma - symptoms get worse if untreated
COPD - no hereditary links
Asthma - some hereditary links
COPD - frequent chest infections
Asthma - less increased freq of chest infections
COPD - presents in older patients
Asthma - any age
What % of COPD patients are smokers?
What % of smokers develop COPD?
90%
15%
What is thought to be a contributory factor in causing non-smokers to develop COPD?
Exposure to small aerosol particles
E.g. concern about air pollution in city centres due to fine particle aerosols from diesel motors
How much as the incidence of COPD risen over the last 10 years?
30%
How do tissue changes in COPD patients differ from those in asthmatics?
What is the predominant inflam cell found in the lungs of COPD patients?
Neutrophil
What feature common to asthma patients does not effect COPD patients?
Thickening of smooth muscle in the bronchiole wall
What should COPD be thought of as?
An exaggerated irritant response that leads to an inflammatory response
What are the characteristics of parasympathetic tone?
How does the body respond to irritation in the lung?
Why doesn’t this work?
Increasing parasympathetic tone to reduce exposure to atmospheric irritant
Source of irritation is within the lung not external to it and increase in ACh causes bronchoconstriction
What is one cause of hyper-responsiveness which is present in patients with both asthma and COPD?
Loss of integrity of protective epithelial cell lining
Reduces barrier between irritant receptors and atmosphere, increasing likelihood of irritant response
What causes long-term swelling (oedema) of bronchial wall?
Increased vascular permeability during inflam for ease of access for immune cells
In what patients is damage to the alveolar extracellular matrix in the lung prevalent?
COPD and severe asthma patients