Prevention of asthma during the first 5 years of life: A randomized controlled trial

University of Sydney, Sydney, New South Wales, Australia
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 08/2006; 118(1):53-61. DOI: 10.1016/j.jaci.2006.04.004
Source: PubMed

ABSTRACT Early life exposures may be important in the development of asthma and allergic disease.
To test house dust mite (HDM) avoidance and dietary fatty acid modification, implemented throughout the first 5 years of life, as interventions to prevent asthma and allergic disease.
We recruited newborns with a family history of asthma antenatally and randomized them, separately, to HDM avoidance or control and to dietary modification or control. At age 5 years, they were assessed for asthma and eczema and had skin prick tests for atopy.
Of 616 children randomized, 516 (84%) were evaluated at age 5 years. The HDM avoidance intervention resulted in a 61% reduction in HDM allergen concentrations (microg/g dust) in the child's bed but no difference in the prevalence of asthma, wheeze, or atopy (P > .1). The prevalence of eczema was higher in the active HDM avoidance group (26% vs 19%; P = .06). The ratio of omega-6 to omega-3 fatty acids in plasma was lower in the active diet group (5.8 vs 7.4; P < .0001). However, the prevalence of asthma, wheezing, eczema, or atopy did not differ between the diet groups (P > .1).
Further research is required to establish whether other interventions can be recommended for the prevention of asthma and allergic disease.
House dust mite avoidance measures and dietary fatty acid modification, as implemented in this trial during infancy and early childhood, did not prevent the onset of asthma, eczema, or atopy in high-risk children.

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Available from: Karen L Webb, Aug 24, 2015
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    ABSTRACT: Resum:Aquesta tesi doctoral consisteix en una sèrie de deu articles (8 publicats y 2 en premsa) basats en dades recollides a lestudi AMICS (Asthma Multicentre Infant Cohort Study), portat a terme a Ashford (UK) a Barcelona y a Menorca. A més dels propis articles, sinclouen una introducció i una discussió generals per a mostrar de forma conjunta les troballes i posar-les en el context de levidència científica actual. També sinclou un apartat sobre les implicacions dels resultats obtinguts tant per la recerca etiològica de lasma com per a la salut pública, així com una llista de recomanacions finals. Des de lany 1997 soc el responsable del estudi de cohort AMICS a Menorca, que ha comptat amb diverses beques del Ministeri de Sanitat i Consum, de la Comunitat Europea i duna fundació privada. Lobjectiu inicial principal del projecte europeu era mesurar el paper del aeroal.lergens domèstics més comuns en el procés diniciació de latòpia i lasma. La cohort de Menorca va ampliar el seus objectius incloent dades addicionals sobre dieta i nivells dorganoclorats a la sang. El projecte continua a Menorca i en el moment de presentar la tesi sestà realitzant el seguiment del 9 anys.Abstract:The present doctoral thesis consists of a series of ten articles (8 published and 2 in press) based on data collected from the Asthma Multicentre Infant Cohort Study (AMICS), carried out in Ashford (UK) and Barcelona and Menorca (Spain). In addition to the articles themselves, a general introduction and a general discussion are included to put together the findings of the articles in the light of present scientific evidence. A section on the implications for the etiologic research of asthma and for public health and a list of final conclusions are also included. I have been responsible of the AMICS cohort in Menorca since its origin in 1997, which has been funded by different grants from the Spanish Ministry of Health, the European Commission and a private foundation. The main initial objective of the European project was to measure the role of common domestic aeroallergens in the inception of atopy and asthma. The Menorca cohort extended its objectives including additional data on dietary habits and blood levels of organochlorine compounds. The project continues in Menorca and at the moment of presenting this thesis the 9 years follow-up work is being carried out.
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