Children with asthma are less likely to finish school and to work in non-manual occupations

The research also suggests that when this group of children grow up, they are less likely to work in certain non-manual occupations such as police officer, clerk or foreman.

Researchers behind the study say these results suggest children with asthma are disadvantaged in education and in their future work.

The research was presented by Dr Christian Schyllert, a clinician at Karolinska University Hospital in Stockholm, Sweden, and a PhD student at Umeå University. He explained: "Asthma is one of the most common chronic diseases among children and we know that it can interfere with daily life and affect school attendance. However, we know a lot less about the impact childhood asthma has on subsequent life chances in adulthood."

The research was based on children living in three districts in Sweden. In 1996, all children aged between seven and eight years were invited to participate in the study and 97% agreed. Participants were followed-up at age 11-12, 19 and 27-28 years. By 2015, researchers were still in contact with 2,291 (59%) of participants.

At the start of the study and at each follow-up, researchers noted whether children had asthma. This meant they had been diagnosed with the condition by a doctor, and suffered wheezing or had taken asthma medication during the previous 12 months. Children were considered to have 'early-onset, persistent asthma' if they were first diagnosed before the age of 12 years and were still suffering with asthma at 19 years old.

Researchers then compared this information with data on when children left education and which occupations they entered. They took into account other factors, such as sex, body weight and smoking, that could have an influence on education and work.

The analysis showed that children with early-onset persistent asthma were three and half times more likely than children without asthma to leave school at the age of 16 with only basic education. They were also twice as likely to drop out of university before completing three years of study.

In terms of their careers, children with early-onset persistent asthma were less than half as likely to enter non-manual occupations, including clerk, nursing assistant, police officer, musician and foreman.

Dr Schyllert said: "This study suggests that children who are diagnosed with asthma when they are young and continue to suffer with the condition as they grow up have worse life chances when it comes to their education and their future jobs.

"We can't tell from this study exactly why this is the case, but other research indicates that children with asthma have lower school attendance and this might lead to asthmatics being unable to remain in education. It could also be that people with poorly-controlled symptoms are less inclined to enter certain occupations, especially those requiring stamina, or jobs where they might be exposed to possible asthma triggers, such as dust or vapours."

Dr Schyllert and his colleagues will continue studying the link between asthma and socioeconomic status. He hopes to follow up the same group in another ten years, when the subjects will be 35 years old. He would also like to study a similar cohort born ten years later, to see if there have been any changes over time.

He added: "Although asthma can be effectively treated with inhaled medications, such as corticosteroids and bronchodilators, sticking to a treatment regime can be difficult, especially for teenagers.

"Until we know more about exactly why childhood asthma effects education and job prospects, the key message for families is try to ensure children stick to their asthma treatments and to speak to a doctor if symptoms aren't under control."

Professor Daiana Stolz of University Hospital Basel in Switzerland is Chair of the European Respiratory Society Education Council and was not involved in the study. She said: "Asthma is a common condition in children and it's important that we understand not only how it affects people in childhood, but also their health and their prospects in adulthood. This study suggests that being diagnosed with asthma at a young age and continuing to suffer with the condition puts children at a disadvantage in education and subsequently when they enter the workplace.

"We need more research to understand why this is the case and what we can do about it, but in the meantime, we need to support children and their families to ensure asthma symptoms are controlled with appropriate treatment and care."