Exercise induced asthma

Some patients may experience asthma which is induced by exercise, and may have few or no symptoms at other times.

Exercise-induced asthma is asthma brought on by physical exertion. For most patients physical activity is an important precipitant and in children it may be the only significant precipitant (1,2).

• typical asthma symptoms (in some instances a troublesome cough) is seen in patients which resolves spontaneously within 30-45 minutes
• symptoms rarely occurs during exercise and typically develop within 5-10 minutes after completing exercise
• some forms of exercise such as running are more potent triggers while swimming is the least likely exercise to provoke exercise-induced asthma (2)
• may occur at any climatic condition - but is more likely to develop when patients are breathing dry, cold air (less common in hot, humid conditions) (1)

Diagnosis can be achieved by observing a rapid improvement

• of post exertion symptoms after inhaled beta2 agonist use or
• prevention of symptoms by pretreatment with an inhaled beta 2 agonist before exercise (1)

Exercise induced symptoms may be the only presenting feature in some asthmatic children. In these patients (or in case there is a doubt about the diagnosis) exercise testing can be easily performed to establish a firm diagnosis of asthma (1).

References:

• (1) Global Initiative for Asthma (2010). Global Strategy for Asthma Management and Prevention
• (2) John Rees, Dipak Kanabar, Shriti Pattani. ABC of Asthma, 6th Edition