Asthma and allergens

Abstract

Asthma is a heterogeneous disease that is influenced by multiple factors including the environment, genetics, pollution, infection, and diet. Atopy, defined as a predisposition to developing allergic sensitization, is a strong predisposing factor for the development of asthma, and for over two decades, there has been increasing evidence that specific allergens can have a causative role in the development of asthma. Environmental allergen sensitivity can also play an important role in the severity and treatment of asthma. The percentage of patients with asthma sensitized to ≥1 environmental allergen approaches 80%, and atopy may be the causative factor in over 50% of asthma cases. An increased exposure to allergens in sensitized individuals can lead to more asthma morbidity and increased health-care utilization. While many allergens are found indoors, the primary aeroallergens to which asthmatics are sensitized include house-dust mites, cats, dogs, mice, cockroaches, and mold (Table 10.1). This chapter will describe specific indoor allergens, highlighting their roles in asthma, and discuss strategies for their avoidance and environmental remediation.