The
Outlook on Asthma
About 300 million people worldwide suffer from asthma, one of the most common
chronic diseases affecting both children and adults. The 2004 Global Burden of
Asthma Report warns that an additional 100 million will be diagnosed with
asthma by 2025. Its prevalence is on the rise as societies become increasingly
urbanized. Each year, asthma accounts for an estimated 250,000 deaths
worldwide, some of which could have been prevented.
Asthma is a respiratory condition that affects an estimated that 300 million people in the world. While death rates for asthma are falling more individuals are developing this disorder, especially children. In asthma the airways (bronchial tubes) that carry air in and out of your lungs are very sensitive (allergic) to some substances in nature or the environment. The allergic substances act as an asthma trigger and may include, dust, pollen, feathers, pet hair or certain foods but there are also non-allergic triggers like, cold and flu viruses, cold weather, exercise or even stress which can irritate the bronchial tubes.
In response to the asthma trigger several reactions take place in the bronchial
tubes leading to an asthmatic attack. When this happens the individual will
experience body signals (symptoms) such as, coughing, wheezing, chest tightness
and trouble breathing. More specifically, during an attack smooth muscle cells,
blood vessels and mucous glands lining the bronchial wall overreact. The smooth
muscles contract severely (bronchospasm), the blood vessels dilate and swell
(inflammation) and finally the mucous glands produce thick phlegm. These
actions, as shown in Figure 1 below, severely reduce the opening of the
bronchial tubes making it difficult to breathe and for the lungs get less air.
In some cases, the thick phlegm may completely block off the movement of air to
the lungs.
Asthma symptoms which can range from mild to severe exist in two states, chronic and acute, and may also vary with the season. During the chronic state of asthma the symptoms do not bother the individual and you feel okay. In contrast, for the acute state, symptoms like coughing and difficulty breathing may occur more often and feel much worse than normal. The change in the level and/or amount of symptoms is a sign that the condition is getting bad and an asthma attack could be developing. Medical attention is needed right away in such situations. Death can occur from an asthmatic attack if the correct medications are delayed.
It is important to note that asthma can be treated under the care of a physician and the person can live well. Individuals who experience any of the symptoms as shown in Table 1 should see a physician to find out if they have asthma or not.
Table 1: Asthma Symptoms*
Coughing |
usually
more at night and either with or without phlegm |
Trouble breathing |
|
Wheezing |
if
present, generally occurs at night and/or early morning |
Chest tightness or pressure |
|
*While common these symptoms do not occur in all asthmatics. The level and/or
amount of symptoms differ among individuals with asthma, they come and go and
there is no set pattern, but during an asthma attack the symptoms become worse.
References
Bousquet J and Khaltaev. Global surveillance, prevention and control of chronic
respiratory diseases: a comprehensive approach. World Health Organization,
2007.
Brahman SS. The global burden of asthma. Chest 2006; 130:4S-12S.
Yawn BP. Factors accounting for asthma variability: achieving optimal symptom
control for individual patients. Prim Care Resp J 2008; 17:138-147.
Wark PAB and Gibson PG. Asthma exacerbations. Review Series 3: pathogenesis.
Thorax 2006; 61:901-915.
American Academy of Allergy, Asthma and Immunology -www.aaaai.org/media/resources
Useful Links
asthma.wegohealth.com/all_topic_topicpages.html
www.asthmameds.ca/whatisasthma.php
www.mayoclinic.com/health/asthma/DS00021
www.en.wikipedia.org/wiki/Asthma
health.nytimes.com/health/guides/disease/asthma/print.html