Asthma risk factors.
BACKGROUND
Bronchial asthma is one of the most common chronic diseases in childhood, with a current prevalence of 6% to 9%, but a prevalence that is increasing at an alarming rate. Asthma is a complex genetic disorder with strong environmental influence. It imposes a growing burden on our society in terms of morbidity, quality of life, and healthcare costs. Despite large-scale efforts, only a few asthma genes have been confirmed, suggesting that the genetic underpinning of asthma is highly complex.


METHODS
A review of the literature was performed regarding atopic and nonatopic asthma risk factors, including environmental risk factors and genetic studies in adults and children.


RESULTS
Several environmental risk factors have been identified to increase the risk of developing asthma such as exposure to air pollution and tobaccos smoke as well as occupational risk factors. In addition atopy, stress, and obesity all can increases the risk for asthma in genetically susceptible persons.


CONCLUSIONS
Asthma represents a dysfunctional interaction with our genes and the environment to which they are exposed, especially in fetal and early infant life. The increasing prevalence of asthma in all age groups indicate that our living environment and immunity are in imbalance with each other reacting with airway inflammation to the environmental exposures and often non-harmful proteins, such as allergens causing the current "asthma and allergy epidemic." Because of the close relationship between asthma and chronic rhinosinusitis, it is important that otolaryngologists have a good understanding of asthma, the etiologic factors associated with disease, and its evaluation and management.
Department of Otorhinolaryngology-Head and Neck Surgery, Temple University, Philadelphia, PA.
Elina
E
Toskala
Department of Otorhinolaryngology-Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
David W
DW
Kennedy
D001249:Asthma / Q000209:etiology / Q000235:genetics; D004777:Environment; D020022:Genetic Predisposition to Disease; D006801:Humans; D012307:Risk Factors
air pollution; allergens; asthma; atopy; environmental risk factors; epigenetics; genetic risk factors; hygiene hypothesis; microbes; risk factors