Related Experiment Videos
On early sensitization to allergens and development of respiratory symptoms
D Sherrill1, R Stein, M Kurzius-Spencer
1Respiratory Sciences Center, University of Arizona, College of Medicine, Tucson, AZ 85724, USA.
Insights
Early allergic sensitization in children significantly increases the risk of developing wheezy symptoms later in life. However, sensitization after age 8 does not appear to be a risk factor for childhood asthma development.
Area of Science:
- Pediatric Allergy and Immunology
- Epidemiology of Respiratory Diseases
- Asthma Pathogenesis
Background:
- Childhood environmental exposures and early life events are implicated in asthma development.
- Investigated the link between early childhood allergic sensitization and subsequent asthma symptoms.
Purpose of the Study:
- To determine if allergic sensitization in early childhood is a significant risk factor for developing asthma symptoms later.
- To differentiate the impact of early versus late sensitization on asthma development.
Main Methods:
- Longitudinal study of children from the Tucson epidemiology study of obstructive airways disease.
- Analysis of respiratory symptom data over 20 years, correlated with allergen skin tests performed before and after age 8.
Main Results:
- Children sensitized to allergens before age 8 were significantly more likely to report wheeze and shortness of breath.
- No increased risk of asthma symptoms was observed in children sensitized after age 8 compared to unsensitized children.
Conclusions:
- Early childhood allergic sensitization (before age 8) is a significant risk factor for developing wheezy symptoms.
- Late childhood sensitization (after age 8) does not appear to be a risk factor for developing these asthma symptoms.
Background:
Various studies have suggested that a sequence of events occurring in childhood may affect the development of asthma in susceptible individuals. We have investigated whether early childhood sensitization to aeroallergens is an important risk factor in the later development of asthma symptoms.
Objective And Methods:
In this study we examine this issue in children enrolled in the Tucson epidemiology study of obstructive airways disease, who had at least two allergen skin tests, one before and one after 8 years of age. Respiratory symptom data were available from 12 survey questionnaires, spanning a period of 20 years. During the first, sixth, seventh and eleventh surveys, skin tests were performed with commercially available allergens.
Conclusion:
As compared with children who were sensitized after 8 years of age, children over 8 years who were sensitized to any allergen before age 8 years were significantly more likely to report shortness of breath with wheeze (SOBWZ), wheeze apart from colds or wheeze most days (OR = 4.1 SOBWZ; OR = 3.88 WZ apart from colds; and OR = 2.83 WZ most days). Children who were sensitized after 8 years were no more likely to have the symptoms described above than children who were never found to be sensitized. Based on these results we conclude that early allergic sensitization is a significant risk factor for later development of wheezy symptoms, where as late sensitization is not.