Children with asthma are most likely to be admitted to hospital in September than any other time of the year.
Hospital admissions for under-16s in England were 58 per cent higher during that month last year, according to data from the NHS Information Centre.
The same phenomenon occurred the previous September, when admission rates were more than double the monthly average for the year.
Peak: Figures released today show children with asthma are more likely to be admitted to hospital in September than any other month (posed)
Experts have called for further investigation into the seasonal surge, but say it could be linked to poorer control of the condition during the summer holidays combined with stress and exposure to infections when children return to school.
An analysis of data for 12 months from May 2009 to April 2010 found each month, on average, there were 2,320 hospital admissions for asthma among children under the age of 16.
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But in September 2009 there were 3,670 admissions among under-16s – a 58 per cent rise. Of these, 2,090 were for children aged five and under. For the 12 months from May 2008 to April 2009, the average under-16 admission figure was 2,380.
In September 2008 the figure was 4,820 (103 per cent higher), of which 2,780 cases were for children aged five and under.
Hospital admissions among older age groups do not follow the same pattern.
Asthmatics are less likely to be admitted when they are older, with admission rates among more senior age groups peaking in October or December.
Tim Straughan, chief executive of the NHS Information Centre, said: ‘Although provisional, these figures provide a useful insight at a national level into the admissions passing through our hospital doors in England and also into possible shifts in trend during the different seasons.
‘These figures appear to highlight September as a hotspot for asthma admissions among our very young children, which may prompt possible investigation as to why this may be.’
Experts at the Asthma UK charity said children were at extra risk at the start of the school year for a number of reasons, but action by parents and teachers can prevent some of the problems.
Head nurse Erica Evans said: ‘We know that children’s admissions for asthma peak in September, which coincides with the start of the new school year.
'There are a number of possible factors, including the spreading of colds and viruses, the potential stresses that a new school term can bring and children not taking their regular preventer medicine over the summer holidays.
‘It’s essential that parents and school staff work together during the school year to make sure that asthma is well managed and to avoid unnecessary hospital admissions for the condition.’
A spokesman for the Department of Health said: ‘We are determined to improve patient outcomes in asthma, as with all other areas of NHS care.
‘This includes helping commissioners understand what a good quality service looks like, ensuring information on asthma is accurate, and testing different models of care for people with asthma.’