The introduction of smokefree legislation in July 2007 led to a sustained drop in children being admitted to hospital for asthma in England.

The number of children admitted with symptoms plummeted by 12.3 per cent in the year after smoke-free laws were implemented, according to a new study published in the journal Pediatrics.

Childhood asthma admissions remained on a downward trajectory in subsequent years, suggesting the benefits of the legislation were sustained in the long-term, NHS statistics show.

Prior to making clubs, pubs, restaurants and all other enclosed public places smokefree, hospital admissions for children suffering a severe asthma attack rose by an average of 2.2 per cent per year - peaking at 26,969 admissions in 2006-2007.

The upward trend reversed immediately once the law came into force, with 6,802 fewer children admitted to hospital with asthma in the first three years of the legislation, researchers at Imperial College London said.

There were lower admission rates among boys and girls of all age groups, and the reductions were seen among children from affluent and less well-off background, and both urban and rural regions.

Hospital admissions for childhood asthma fell after smoke-free legislation was introduced in Scotland and North America, earlier studies revealed.

Study leader Dr Christopher Millett, of the School of Public Health at Imperial College London, said there was clear evidence that eliminating smoking in public places has resulted in "substantial population health benefits" in England.

As well as reducing hospital admissions for childhood asthma, the smoke-free legislation has reduced the rate of heart attacks.

Dr Jean King, Cancer Research UK's director of tobacco policy, said the finding was "further evidence of the success" of smoke-free laws in protecting the health, particularly among workers and vulnerable groups like children with asthma.

"Although we won't see a reduction in cancer rates for some years to come, the short and medium term health gains we have seen are very encouraging," she added.

"We must press on to protect the next generation from the harm caused from smoking by ending all marketing to children through putting tobacco in plain, standardised packs."

Source: CRUK