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Asthma - Background information
What is asthma?
- Asthma is a chronic inflammatory condition of the airways, the cause of which is not completely understood. The airways are hyper-responsive and constrict easily in response to a wide range of stimuli. This may result in coughing, wheezing, chest tightness, and shortness of breath:
- Narrowing of the airways is usually reversible (either spontaneously or with medication), leading to intermittent symptoms, but in some people with chronic asthma, the inflammation may lead to irreversible airflow obstruction.
- Asthma can vary markedly in severity, clinical course, and response to treatment.
- Acute asthma exacerbation is a term used to describe onset of severe asthma symptoms.
- Work-aggravated asthma is pre-existing asthma that is aggravated non-specifically by dust and fumes at work.
- Occupational asthma is asthma due to exposure to specific substances at work.
- Exercise-induced asthma is asthma brought on by physical exertion. For most people, it is an indication of poorly controlled asthma.
[Newman Taylor, 2003; SIGN and BTS, 2009]
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