Causes and Triggers of Asthma
Those people who readily develop antibodies of IgE class against common materials present in the environment can
also develop asthma.
Such antibodies are present in 30-40% of the western population, and there is a link between serum IgE levels
and both the prevalence of asthma and airway responsiveness to histamine or methacholine.
Genetic and environmental factors affect serum IgE levels and may turn out to play a key role in the development
of asthma.
Early childhood exposure to allergens and maternal smoking can also cause IgE production. It has been suggested
growing up in a relatively clean environment can predispose towards an IgE response to allergens. On the other
hand, growing up in a dirtier environment may allow the immune system to avoid developing allergic responses!
Occupational sensitizers
Over 200 materials encountered in the workplace are recognized as giving rise to occupational asthma. These are
usually recognized as occupational diseases in the western world.
Asthma sufferers in insurable employment who can prove their workplace contributed to their condition are
eligible for statutory compensation provided they apply within 10 years of leaving the occupation in which the
asthma developed (UK).
The risk of developing occupational asthma increases in smokers.
The proportion of workers developing occupational asthma depends on their exposure, so the correct enclosure of
industrial processes and appropriate ventilation can greatly reduce the risk of contracting Asthma
Non-specific factors Characteristic feature of bronchial hyper reactivity in asthmatics mean as
well as reacting to specific antigens their airways will also respond to a wide variety of non-specific
stimuli.
Cold air and exercise Many asthmatics may experience an attack of wheezing after they have
completed prolonged or non-stop exercise especially in a cold environment. The attack doesn't occur during the
middle of their exercise period but towards the end. The inhalation of cold, dry air can also cause an asthmatic
attack.
Environmental Pollution
Contact with cigarette smoke, car exhaust fumes, strong perfumes or high concentrations of dust in the atmosphere
can be strong factors in causing an asthmatic attack.
Epidemics Major epidemics of asthma have been recorded when large amounts of allergens have
been released into the air, (e.g. there was a soy bean epidemic in Barcelona.)
Further insignificant epidemics of asthma have occurred during periods of heavy atmospheric contamination in
industrialized areas which is caused by the presence of high concentrations of sulphur dioxide, ozone and nitrogen
dioxide in the air.
Food Certain foods such as wine can trigger an asthma attack.
Emotion Asthma is also influenced by certain emotions such as laughing, crying etc. But
there is no proof people with asthma are any more psychologically disturbed than their non-asthmatic peers.
Drugs Used with Asthma
Non-steroid anti-inflammatory drugs (NSAIDs). NSAIDs, chiefly aspirin, have a major role in the development and
precipitation of attacks in approximately 5% of people with asthma.
Immediate asthma This is the most common response. An attack begins within minutes of
contact with the allergen, reaches its maximum in 15-20 minutes and subsides after 1 hour.
Late-phase reactions
Following an instantaneous reaction many asthmatics may develop more prolonged and sustained attacks that respond
inadequately to the inhalation of bronchodilator drugs.
Dual asthmatic response
This is a combination of an early reaction followed by a late reaction.
Recurrent asthmatic reactions Development of a late-phase response is associated with
increases in underlying level of airway hyper reactivity that individuals can show with systematic episodes of
asthma on subsequent days.
|