Doctors in Southampton have discovered that protecting babies from highly allergenic foods and dust mites in their first year of life can prevent the development of asthma during childhood.
In a groundbreaking study, Professor Hasan Arshad, a consultant in allergy at Southampton General Hospital, found that a child's risk of developing the condition is reduced by more than half if their contact with common triggers of allergy from birth to 12 months is controlled.
"Although genetic links are arguably the most significant risk factor for asthma in children, environmental factors are the other critical component," said Prof Arshad, who is also director of the David Hide Asthma and Allergy Research Centre on the Isle of Wight.
"Although this was a small study, we have found that the risk of developing asthma at some point during childhood is reduced by more than 50% if we introduce control of a child's environment."
His team assessed 120 patients with a family history of allergy who were recruited at birth 23 years ago to find out whether or not breastfeeding mothers and their children who followed a diet of strict avoidance of dairy products, eggs, soya, fish and nuts, along with the use of vinyl mattress covers and pesticides to kill dust mites, had a lower risk of developing asthma.
They performed follow-up at ages two, three, four, eight and 18 and found that while only 11% of those in the prevention group had developed asthma by age 18, more than a quarter (27%) of those who were naturally exposed to substances linked to allergic reactions had the condition.
He added: "By introducing a combined dietary and environmental avoidance strategy during the first year of life, we believe the onset of asthma can be prevented in the early years and throughout childhood up to the age of 18.
"Our finding of a significant reduction in asthma using the dual intervention of dust mite avoidance and diet modification is unique in terms of the comprehensive nature of the regime, the length of follow-up and the size of the effect observed."
The research, published in the journal Thorax and funded by the National Institute for Health Research (NIHR), is the first study to show a persistent and significant reduction in asthma throughout childhood.
Prof Arshad, who is also chair in allergy and immunology at the University of Southampton and is based at the NIHR Southampton respiratory biomedical research unit, said there was now an urgent need to replicate the findings in a large multicentre study.
Posted on Thursday 21 March 2013