Obesity epidemic may be fuelling the rise in childhood asthma

Researchers say it is possible weight gain is driving the condition  - Alamy
Researchers say it is possible weight gain is driving the condition - Alamy

The obesity epidemic may be fuelling the rise in childhood asthma, a study suggests.

Researchers in the US discovered that obese youngsters were 30 per cent more likely to develop the lung condition than children of a healthy weight, while being overweight raised the risk by 17 per cent.

The team at Duke University in North Carolina, studied the medical records of 500,000 children as they visited the doctor between 2009 and 2015, a total of 19 million appointments.

The results suggest that one in 10 asthma cases are linked to weight gain. If the findings were replicated in Britain - where 1.1 million under 18s have asthma -  it would mean more than 100,000 children might have avoided the illness if they were a healthy size.

Although previous research has suggested that children with asthma are more likely to be obese because they are unable to exercise, the authors of the new study said it now seemed that the weight itself that was driving the condition.

“I think it's reasonable to be concerned that it's a causal relationship," said Dr Jason Lang, associate professor of pediatrics at Duke and the study's lead author.

“It appears becoming overweight or obese as a child significantly increases your risk of developing asthma, and it's a significant increase, directing attention again to the importance of preventing obesity at an early age.

“Obesity may be the only risk factor for childhood asthma that could be preventable. This is another piece of evidence that keeping kids active and at a healthy weight is important.”

It is thought that too much weight stops the lungs expanding properly causing people to take smaller shallower breaths which can aggravate the airways. It may also trigger inflammation in the body which can spark asthma attacks.

Approximately one in 11 children suffer from asthma in the UK and across all ages roughly 1,410 people die from the condition each year. Since 1955 the prevalence of asthma has increased by up to three fold.

Research published by Public Health England this year suggests that in some parts of Britain nearly half of children are now dangerously overweight. In the London borough of Brent, in 44 per cent weigh too much.

Overall, 32.4 per cent of children are overweight or obese by the age of 11 - a rise from 30 per cent in 2006/7.

The figures are worst for boys, with 36 per cent classed in these categories - a rise from 33.2 per cent a decade ago.

The PHE statistics also showed that boys are most likely to be classed as “severely obese” - with almost 5 per cent of boys reaching this point by the end of primary school, compared with 3.3 per cent of girls.

Chief Scientific Officer Dr Terri Finkel at at Nemours Children's Hospital in Orlando who participated in the study said: "Paediatric asthma is among the most prevalent childhood conditions and comes at a high cost to patients, families and the greater health system.

"There are few preventable risk factors to reduce the incidence of asthma, but our data show that reducing the onset of childhood obesity could significantly lower the public health burden of asthma"

“Addressing childhood obesity should be a priority to help improve the quality of life of children and help reduce paediatric asthma.”

The research was published in the journal Pediatrics.