The prevalence of asthma in Australia is amongst the highest in the world yet no trials of primary prevention have been conducted which address the most common known causative agent (housedust mite allergens) and the most common known protective factor (dietary omega-3 fatty acids). Until the effectiveness of interventions which address these factors is certain, the value of the wide array of advice given to asthmatics by various health institutions will not be known. We are applying to continue ....The prevalence of asthma in Australia is amongst the highest in the world yet no trials of primary prevention have been conducted which address the most common known causative agent (housedust mite allergens) and the most common known protective factor (dietary omega-3 fatty acids). Until the effectiveness of interventions which address these factors is certain, the value of the wide array of advice given to asthmatics by various health institutions will not be known. We are applying to continue the Childhood Asthma Prevention Study (CAPS) which has been underway since mid-1997. CAPS is a randomised controlled trial in which 616 infants at high risk of developing asthma because of a family history have been enrolled. The interventions include allergen reduction and dietary supplementation with omega-3 fatty acids. The interventions are designed to have maximum effect but be simple to implement by parents. Several measures of compliance are being collected and regular contact is maintained though telephone calls and frequent home visits. Objective and subjective measurements of exposures, atopy, diet and asthmatic symptoms are being collected at 3 month intervals and at medical assessments when the children are 18 months, 3 and 5 years old. It is essential that we continue the study until all children are aged 5 and we will be able to test conclusively whether the interventions have had a positive effect. If so, CAPS will form the basis for a nationwide public health campaign which will have the potential to reduce the incidence of childhood asthma in Australia.Read moreRead less
Environmental Influences On Allergic Airways Disease From Birth To 8yrs: Long-term Outcomes Of A Randomised Trial (CAPS)
Funder
National Health and Medical Research Council
Funding Amount
$530,000.00
Summary
The prevalence of asthma in Australia is among the highest in the world yet no trials of primary prevention have been conducted which address the most common known causative agent (housedust mite allergens) and the most common known protective factor (dietary omega-3 fatty acids). Until the effectiveness of interventions which address these factors is certain, it will not be possible to give confident advice about how to prevent asthma. We are applying to continue follow up of the cohort of the ....The prevalence of asthma in Australia is among the highest in the world yet no trials of primary prevention have been conducted which address the most common known causative agent (housedust mite allergens) and the most common known protective factor (dietary omega-3 fatty acids). Until the effectiveness of interventions which address these factors is certain, it will not be possible to give confident advice about how to prevent asthma. We are applying to continue follow up of the cohort of the Childhood Asthma Prevention Study (CAPS) which has been underway since mid-1997. CAPS is a randomised controlled trial in which 616 infants at high risk of developing asthma because of a family history have been enrolled. The interventions include allergen reduction and dietary supplementation with omega-3 fatty acids. The interventions are designed to have maximum effect but be simple to implement by parents. Objective and subjective measurements of exposures, atopy, diet and asthmatic symptoms are being collected at 3 month intervals and at medical assessments when the children are 18 months, 3 and 5 years old. The interventions are stopped at age 5 years. The continued follow up of the cohort to age 8 will enable us to test conclusively if the interventions have had a positive effect. If so, CAPS will form the basis for a nationwide public health campaign which will have the potential to reduce the incidence of childhood asthma in Australia.Read moreRead less
Exploration Of Exposures Associated With Bedding That Are Risks For Childhood Allergy And Asthma Symptoms
Funder
National Health and Medical Research Council
Funding Amount
$263,500.00
Summary
Asthma prevalence in Australia has doubled in the last 20 years, with 1 in 4 children now affected. House dust mites are probably the single most important allergen associated with asthma. The prevalence of mite allergy is linked to exposure, and such allergy when combined with high exposure, is a potent risk factor for asthma exacerbations. The current international advice for managing mite-allergic asthma, strongly advocates the use of bedding encasings as the best way to reduce exposure. Howe ....Asthma prevalence in Australia has doubled in the last 20 years, with 1 in 4 children now affected. House dust mites are probably the single most important allergen associated with asthma. The prevalence of mite allergy is linked to exposure, and such allergy when combined with high exposure, is a potent risk factor for asthma exacerbations. The current international advice for managing mite-allergic asthma, strongly advocates the use of bedding encasings as the best way to reduce exposure. However, three recent major trials using encasings and a meta-analysis of earlier trials all fail to show a clinical benefit. One of the applicants (ET) recently showed, using expertise in measuring personal exposure, that these encasings, as used, fail to significantly reduce aeroallergen exposure. By contrast, 3 recent Australian studies, involving the applicants, AK, ALP and NG showed that feather bedding compared to synthetic bedding, was strongly protective for asthma - the opposite of public advice. The suggested mechanisms involve reduced exposure to mite allergens, or altered exposure to bacterial endotoxin, but persuasive experimental support is lacking. We also propose a novel hypothesis that feather exposure may induce allergic 'tolerance'. Currently there is a lack of certainty about valid approaches to prevent asthma, and the Global Initiative for Asthma has described the need to understand mechanisms and improve interventions as urgent. This project is an ideal opportunity to combine the expertise of the CIA (ET) in measuring airborne exposures (mite, endotoxin, proteins) with that of the others who have expertise in children's asthma, and who are already involved in two large clinical trails involving different bedding and allergen avoidance. Our measurements of these bedding exposures and their clinical outcomes will provide, for the first time, a quantitative basis to refine public health allergen-based interventions to prevent and manage asthma.Read moreRead less