News Release

Twins are significantly less likely to have asthma than singletons

Peer-Reviewed Publication

BMJ

Reduced risk of hospital admission for childhood asthma among Scottish twins: record linkage study

Twins run less risk of developing asthma than singletons, reports a study in this week's BMJ.

Strachan and colleagues analysed the admission data for respiratory illness of twins and singletons up to the age of 10 among Scottish hospitals. The study covered the years 1981 to 1994.

They found that twins' overall risk of admission for respiratory disease was significantly lower than that of singletons. Although twins were more likely to be admitted for acute bronchitis and bronchiolitis, they were much less likely than singletons to be admitted to hospital for asthma.

The authors conclude that the difference in admission rates might have been exaggerated if the admission of one twin with asthma led to preventive treatment of the other, but suggest that this is unlikely to explain the large difference in admission rates. Nor can birthweight explain the difference as low birthweight is associated with increased risk of asthma, but twins weigh less than singletons. Rather, they suggest that twinship is a special case of the protective effect of large families on allergies.

###

Contact:
Dr David Strachan, Department of Public Health Sciences, St George's Hospital Medical School, London
Email: d.strachan@sghms.ac.uk



Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.