Asthma remains a leading cause of chronic illness in childhood, and is the most frequent admitting diagnosis in children's hospitals nationwide. It is also the leading cause of school absenteeism, resulting in 5 to 7 days of school absence per year per child in the United States. Moreover, it has the capacity to lead to severe psychosocial disturbances within the child's family.1
The prevalence of and mortality from asthma have been on the rise during the past three decades. Some of the risk factors identified for asthma deaths include underestimation of the severity of asthma, delay in implementing appropriate therapy, and underuse of bronchodilators and corticosteroids. Another factor that may contribute greatly to poor asthma control and increased morbidity is the lack of awareness on the part of health care providers that allergic rhinitis may serve as a harbinger for asthma in a child. As a future general pediatrician who will be responsible for the comprehensive care of children, I have learned that it is not enough to understand the pathophysiology of asthma and be knowledgeable in its effective control and management. I must also be able to identify and effectively treat comorbid conditions such as allergic rhinitis and sinusitis, because these may contribute to chronic inflammation in the lower airway.
In this issue, it was interesting to read about the epidemiologic evidence linking bronchial asthma and allergic rhinitis. I was especially impressed to learn that asthma occurs in as many as 40% of children who have allergic rhinitis.2 Moreover, in children, allergic rhinitis precedes the appearance of bronchial asthma. Numerous studies indicate that both entities share a common pathophysiology in terms of immunopathology, neurogenic mechanisms, and anatomic factors, and these common factors may mediate both upper and lower airway chronic inflammatory activity with resulting bronchial hyperreactivity.
Other evidence has shown that aggressive treatment of upper airway disease results in improvement of asthma in a number of children. Pediatricians should keep in mind that common treatment modalities used for the relief of allergic rhinitis may have a positive influence on lower airway dynamics, thereby improving asthma control. The antihistamine and decongestant therapy, topical steroid therapy, and immunotherapy used for allergic rhmitis have all been shown to decrease lower airway hyperresponsiveness, reduce inflammation, control symptoms of asthma significantly, and, possibly, retard the progression of asthma in children.
As prospective givers of pediatric primary care, we will be exposed to many children with allergic rhinitis in our clinical practices. With knowledge about this disease and its close association with bronchial asthma, we may be able to make a difference in the lives of these children. It is hoped that our awareness of the immunobiologic interrelationship between these two diseases and our understanding of the possible benefits of better asthma control by effective management of allergic rhinitis will contribute to a significant reduction in morbidity and mortality from asthma.
As pediatricians, we must realize that although allergic rhinitis has been traditionally viewed as a benign manifestation, it may serve as a warning for asthma. If, by achieving effective control of this upper airway disease in our office settings, we could spare a child from having either asthma or a worsening of existing asthma, this would be a tremendous contribution. These efforts may be realized as savings in health care costs, reducing the use of potentially toxic medications for asthma control, or a positive influence on the quality of life of the child who is at risk for asthma or has asthma.
The "take home" message for me is that events that transpire in the upper airway from chronic allergies and sinusitis may have a tremendous impact on lower airway allergic disorders such as asthma. The effective management and control of allergic rhinitis and sinusitis may improve asthma control and, it is hoped, lead to asthma prevention.
1. Sly M. Allergic disorders. In: Behrman RE, Kliegman R, Jenson HB, eds. Nelson's Textbook of Pediatrics, 16th ed. Philadelphia: W. B. Saunders; 2000:664.
2. Corren J, Harris A, Aaronson D, et al. Efficacy and safety of loratadine plus pseudoephedrine in patients with seasonal allergic rhinitis and mild asthma. J Allergy Clin Immunol. 1997;100:781-788.