Introduction
Exercise-Induced Asthma (EIA), also known as Exercise-Induced bronchoconstriction (EIB) is a respiratory condition that causes patients to experience shortness of breath, coughing or wheezing immediately after physical exercise (Spooner, Spooner & Rowe, 2009). The condition is common among children, and is often associated with other forms of childhood asthma (Kersten et al, 2012). With such a profound impact, EIA has received a lot of attention from the medical fraternity, with numerous studies being done on it. This paper reviews these studies and other study reviews on EIA and outlines the pathogenesis of the condition, its diagnosis, treatment and management.
Pathogenesis of Exercise-Induced Asthma
The onset of an EIA attack follows a constriction of the airways of the patient after physical exercise. The constriction is caused by loss of water vapor in the bronchi of a patient. This is followed by an increase in osmolarity of the liquid on the surface of the airway leading to an asthma attack. When water shifts from the cells of the epithelium to the airway surface, it causes a release of mediators from the inflammatory cells that cause constriction of the bronchi. Exercising in cold or dry air can lead to an increase in the severity of EIA (Kersten et al, 2012). The attack is also caused by inflammation of the bronchi and a dysfunction of the smooth muscles (Backer & Rasmussen, 2009).
The greatest constriction of the bronchi occurs between 3 and 15 minutes after the patient has rested from the exercise. This phase takes between 20 and 60 minutes to subside. Some patients may experience a refractory period extending to 3 hours, during which more exercise causes less constriction. Factors that influence the severity of the reaction include the severity of asthma, duration and intensity of the exercise or activity, environmental conditions, and the interval of time since the previous exercise (Spooner, Spooner, & Rowe, 2009).
Diagnosis of Exercise-Induced Asthma
EIA occurs when continuous exercise causes the narrowing of the airway resulting in symptoms such as coughing, wheezing, tightness of the chest, premature fatigue and reduced stamina (Spooner, Spooner, & Rowe, 2009). These symptoms are the first indicators of the presence of EIA (hull et al, 2009). The symptoms are also seen to vary from patient to patient (Backer & Rasmussen, 2009). However, for a proper treatment to be given, a proper diagnosis must be done since the symptoms are not conclusive evidence of the presence of EIA. Medical practitioners use bronchoprovocation testing as a method of diagnosing for EIA. The most commom method used is the use of laboratory-based exercise tests (Hull et al, 2009). Other methods used include the trial of an inhaled beta-agonist during exercise, monitoring of the serial peak flow, reversibility testing, electrocardiogram, chest radiograph and use of a full blood count (Hull et al, 2009).
Treatment and control of Exercise-Induced Asthma
Traditionally, EIA has been controlled using nebulized short-acting beta-agonists, an example being salbutamol, which serve the purpose of relieving acute asthma attacks. These medications have, however, been linked to the spread of air borne infections such as H1N1. An alternative to this medication was therefore developed, which is the use of budesonide (formoterol) under the brand name Symbicort, a long- acting beta-agonist. It is in form of an inhaler. A study conducted on its effectiveness showed no significant variation between its effectiveness and the effectiveness of salbutamol, which makes it a better alternative since it carries no risk of infection spread (Chew, Kamarudin, & Hashim, 2012). Spooner, Spooner & Rowe (2009) also propose the use of b-agonosts, stating that they are more effective than anticholigenic medication in inducing bronchial dilation which reverses the constriction effect.
Backer & Rasmussen (2009) propose different treatments and control of EIA, based on the cause of the constriction of the brinchi. For constriction caused by inflammation, he proposes the use of corticosteroids while constriction caused by a dysfunction of the smooth muscles should be treated using a beta-agonist inhaler.
Conclusion
Treatment of EIA is important for active people. It has been seen to enable athletes to participate in any physical activity, allowing them to perform at normal or even above normal levels without the symptoms of the condition hindering their activity. Treatment of the condition also improves the self esteem of the patient (Spooner, Spooner, & Rowe, 2009). This means that even children, who are continuously active, can engage in play and lead normal lives if the condition is controlled through use of the right medication.
References
Backer, V., & Rasmussen, L. (2009). Exercise-Induced Asthma Symptoms and Nighttime Asthma: Are They Similar to AHR? Journal of Allergy, Article ID 378245, Web.
Chew, K. S., Kamarudin, H., & Hashim, C. W. (2012). A randomized open-label trial on the use of budesonide/formoterol (Symbicort®) as an alternative reliever medication for mild to moderate asthmatic attacks. International Journal of Emergency Medicine, 5:16, Web.
Hull, J. H., Hull, P. J., Parsons, J. P., Dickinson, J. W., & Ansley, L. (2009). Approach to the diagnosis and management of suspected exercise-induced bronchoconstriction by primary care physicians. BMC Pulmonary Medicine , 9:29, Web.
Kersten, Elin T.G.; Leeuwen, Janneke C. van; Brand, Paul L.P.; Duiverman, Eric J.; Jongh, Frans H.C. de; Thio, Bernard J.; Driessen, Jean M.M. (2012). Effect of an Intranasal Corticosteroid on Exercise Induced Bronchoconstriction in Asthmatic Children.Pediatric Pulmonology , 47, 27–35, Web.
Spooner, C., Spooner, G., & Rowe, B. (2009). Mast-cell stabilising agents to prevent exercise-induced bronchoconstriction (Review). The Cochrane Library. Web.